diff --git a/app.zip b/app.zip
index 6d23753..c39ea11 100644
Binary files a/app.zip and b/app.zip differ
diff --git a/app/assets/utils/classes/ContactManager.php b/app/assets/utils/classes/ContactManager.php
new file mode 100644
index 0000000..e301e2a
--- /dev/null
+++ b/app/assets/utils/classes/ContactManager.php
@@ -0,0 +1,185 @@
+<?php
+
+/**
+ * ContactManager
+ *
+ * Encapsulates contact and contact type operations:
+ * - Soft-delete with downstream validation
+ *
+ * Note: Methods that modify data do NOT manage their own DB transactions.
+ * Callers are responsible for wrapping operations in dbTransaction() when atomicity is needed.
+ */
+class ContactManager {
+
+    private $pdo;
+    private $company_id;
+
+    public function __construct($pdo, $company_id) {
+        $this->pdo        = $pdo;
+        $this->company_id = $company_id;
+    }
+
+    // ─────────────────────────────────────────────────────────────
+    // Private helpers
+    // ─────────────────────────────────────────────────────────────
+
+    /**
+     * Check if a contact_id is referenced in any active td_stock_* row.
+     * Returns true if blocking stock exists.
+     */
+    private function hasActiveStock(int $contact_id): bool {
+
+        $sth = $this->pdo->prepare(
+            "SELECT table_name FROM information_schema.tables
+             WHERE table_schema = DATABASE()
+               AND table_name LIKE 'td_stock_%'"
+        );
+        $sth->execute();
+        $tables = $sth->fetchAll(PDO::FETCH_COLUMN);
+
+        foreach ($tables as $table) {
+            $sth = $this->pdo->prepare(
+                "SELECT COUNT(*) FROM `$table`
+                 WHERE company_id = :company_id
+                   AND contact_id = :contact_id"
+            );
+            $sth->execute([
+                ':company_id' => $this->company_id,
+                ':contact_id' => $contact_id,
+            ]);
+            if ($sth->fetchColumn() > 0) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Build a log entry array for audit context.
+     */
+    private function buildLogEntry(string $action): array {
+        return [
+            'user_id' => $_SESSION['login_user_id'] ?? null,
+            'dt'      => date('Y-m-d H:i:s'),
+            'login'   => isset($_SESSION['otpTime'])
+                         ? date('Y-m-d H:i:s', $_SESSION['otpTime'])
+                         : null,
+            'action'  => $action,
+        ];
+    }
+
+    // ─────────────────────────────────────────────────────────────
+    // Contact type
+    // ─────────────────────────────────────────────────────────────
+
+    /**
+     * Soft-delete a contact type.
+     *
+     * Blocks if any md_contact references this type.
+     *
+     * @throws Exception if contact type not found or has dependent contacts
+     */
+    public function deleteContactType(int $type_id): void {
+
+        $sth = $this->pdo->prepare(
+            "SELECT id, contact_type, `log` FROM md_contact_type
+             WHERE company_id = :company_id AND id = :id"
+        );
+        $sth->execute([
+            ':company_id' => $this->company_id,
+            ':id'         => $type_id,
+        ]);
+        $row = $sth->fetch(PDO::FETCH_ASSOC);
+
+        if (!$row) {
+            throw new Exception("Contact type not found.");
+        }
+
+        // Block if any contact references this type
+        $sth = $this->pdo->prepare(
+            "SELECT COUNT(*) FROM md_contact
+             WHERE company_id = :company_id
+               AND contact_type = :type_id"
+        );
+        $sth->execute([
+            ':company_id' => $this->company_id,
+            ':type_id'    => $type_id,
+        ]);
+
+        if ($sth->fetchColumn() > 0) {
+            throw new Exception(
+                "Cannot delete — contact type \"{$row['contact_type']}\" " .
+                "still has contacts assigned to it."
+            );
+        }
+
+        // Append delete event to log
+        $log   = json_decode($row['log'] ?? '[]', true) ?: [];
+        $log[] = $this->buildLogEntry('delete');
+
+        // Soft-delete
+        $this->pdo->prepare(
+            "UPDATE md_contact_type
+             SET company_id = company_id * -1,
+                 `log`      = :log
+             WHERE id = :id AND company_id = :company_id"
+        )->execute([
+            ':log'        => json_encode($log),
+            ':id'         => $type_id,
+            ':company_id' => $this->company_id,
+        ]);
+    }
+
+    // ─────────────────────────────────────────────────────────────
+    // Contact
+    // ─────────────────────────────────────────────────────────────
+
+    /**
+     * Soft-delete a contact.
+     *
+     * Blocks if the contact is referenced in any active td_stock_* row.
+     *
+     * @throws Exception if contact not found or referenced in active stock
+     */
+    public function deleteContact(int $contact_id): void {
+
+        $sth = $this->pdo->prepare(
+            "SELECT id, contact_name, `log` FROM md_contact
+             WHERE company_id = :company_id AND id = :id"
+        );
+        $sth->execute([
+            ':company_id' => $this->company_id,
+            ':id'         => $contact_id,
+        ]);
+        $row = $sth->fetch(PDO::FETCH_ASSOC);
+
+        if (!$row) {
+            throw new Exception("Contact not found.");
+        }
+
+        // Block if contact is referenced in any active stock transaction
+        if ($this->hasActiveStock($contact_id)) {
+            throw new Exception(
+                "Cannot delete — \"{$row['contact_name']}\" " .
+                "is referenced in active stock transactions."
+            );
+        }
+
+        // Append delete event to log
+        $log   = json_decode($row['log'] ?? '[]', true) ?: [];
+        $log[] = $this->buildLogEntry('delete');
+
+        // Soft-delete
+        $this->pdo->prepare(
+            "UPDATE md_contact
+             SET company_id = company_id * -1,
+                 `log`      = :log
+             WHERE id = :id AND company_id = :company_id"
+        )->execute([
+            ':log'        => json_encode($log),
+            ':id'         => $contact_id,
+            ':company_id' => $this->company_id,
+        ]);
+    }
+}
\ No newline at end of file
diff --git a/app/assets/utils/classes/ProductManager.php b/app/assets/utils/classes/ProductManager.php
new file mode 100644
index 0000000..e6207c8
--- /dev/null
+++ b/app/assets/utils/classes/ProductManager.php
@@ -0,0 +1,186 @@
+<?php
+
+/**
+ * ProductManager
+ *
+ * Encapsulates product and product category operations:
+ * - Soft-delete with downstream validation
+ *
+ * Note: Methods that modify data do NOT manage their own DB transactions.
+ * Callers are responsible for wrapping operations in dbTransaction() when atomicity is needed.
+ */
+class ProductManager {
+
+    private $pdo;
+    private $company_id;
+
+    public function __construct($pdo, $company_id) {
+        $this->pdo        = $pdo;
+        $this->company_id = $company_id;
+    }
+
+    // ─────────────────────────────────────────────────────────────
+    // Private helpers
+    // ─────────────────────────────────────────────────────────────
+
+    /**
+     * Check if a SKU has any active stock across all td_stock_* tables.
+     * Returns the first blocking table name found, or null if clear.
+     */
+    private function findActiveStock(string $sku): ?string {
+
+        $sth = $this->pdo->prepare(
+            "SELECT table_name FROM information_schema.tables
+             WHERE table_schema = DATABASE()
+               AND table_name LIKE 'td_stock_%'"
+        );
+        $sth->execute();
+        $tables = $sth->fetchAll(PDO::FETCH_COLUMN);
+
+        foreach ($tables as $table) {
+            $sth = $this->pdo->prepare(
+                "SELECT COUNT(*) FROM `$table`
+                 WHERE company_id = :company_id
+                   AND product_sku = :sku"
+            );
+            $sth->execute([
+                ':company_id' => $this->company_id,
+                ':sku'        => $sku,
+            ]);
+            if ($sth->fetchColumn() > 0) {
+                return $table;
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Build a log entry array for audit context.
+     */
+    private function buildLogEntry(string $action): array {
+        return [
+            'user_id' => $_SESSION['login_user_id'] ?? null,
+            'dt'      => date('Y-m-d H:i:s'),
+            'login'   => isset($_SESSION['otpTime'])
+                         ? date('Y-m-d H:i:s', $_SESSION['otpTime'])
+                         : null,
+            'action'  => $action,
+        ];
+    }
+
+    // ─────────────────────────────────────────────────────────────
+    // Product category
+    // ─────────────────────────────────────────────────────────────
+
+    /**
+     * Soft-delete a product category.
+     *
+     * Blocks if any md_product references this category.
+     *
+     * @throws Exception if category not found or has dependent products
+     */
+    public function deleteCategory(int $category_id): void {
+
+        $sth = $this->pdo->prepare(
+            "SELECT id, category, `log` FROM md_product_category
+             WHERE company_id = :company_id AND id = :id"
+        );
+        $sth->execute([
+            ':company_id' => $this->company_id,
+            ':id'         => $category_id,
+        ]);
+        $row = $sth->fetch(PDO::FETCH_ASSOC);
+
+        if (!$row) {
+            throw new Exception("Product category not found.");
+        }
+
+        // Block if any product references this category
+        $sth = $this->pdo->prepare(
+            "SELECT COUNT(*) FROM md_product
+             WHERE company_id = :company_id
+               AND category = :category_id"
+        );
+        $sth->execute([
+            ':company_id'  => $this->company_id,
+            ':category_id' => $category_id,
+        ]);
+
+        if ($sth->fetchColumn() > 0) {
+            throw new Exception(
+                "Cannot delete — category \"{$row['category']}\" " .
+                "still has products assigned to it."
+            );
+        }
+
+        // Append delete event to log
+        $log   = json_decode($row['log'] ?? '[]', true) ?: [];
+        $log[] = $this->buildLogEntry('delete');
+
+        // Soft-delete
+        $this->pdo->prepare(
+            "UPDATE md_product_category
+             SET company_id = company_id * -1,
+                 `log`      = :log
+             WHERE id = :id AND company_id = :company_id"
+        )->execute([
+            ':log'        => json_encode($log),
+            ':id'         => $category_id,
+            ':company_id' => $this->company_id,
+        ]);
+    }
+
+    // ─────────────────────────────────────────────────────────────
+    // Product
+    // ─────────────────────────────────────────────────────────────
+
+    /**
+     * Soft-delete a product.
+     *
+     * Blocks if the product SKU has any active stock across any td_stock_* table.
+     *
+     * @throws Exception if product not found or has active stock
+     */
+    public function deleteProduct(int $product_id): void {
+
+        $sth = $this->pdo->prepare(
+            "SELECT id, product_name, sku, `log` FROM md_product
+             WHERE company_id = :company_id AND id = :id"
+        );
+        $sth->execute([
+            ':company_id' => $this->company_id,
+            ':id'         => $product_id,
+        ]);
+        $row = $sth->fetch(PDO::FETCH_ASSOC);
+
+        if (!$row) {
+            throw new Exception("Product not found.");
+        }
+
+        // Block if active stock exists for this SKU in any warehouse
+        $blocking_table = $this->findActiveStock($row['sku']);
+        if ($blocking_table !== null) {
+            throw new Exception(
+                "Cannot delete — \"{$row['product_name']}\" " .
+                "still has active stock in the system."
+            );
+        }
+
+        // Append delete event to log
+        $log   = json_decode($row['log'] ?? '[]', true) ?: [];
+        $log[] = $this->buildLogEntry('delete');
+
+        // Soft-delete
+        $this->pdo->prepare(
+            "UPDATE md_product
+             SET company_id = company_id * -1,
+                 `log`      = :log
+             WHERE id = :id AND company_id = :company_id"
+        )->execute([
+            ':log'        => json_encode($log),
+            ':id'         => $product_id,
+            ':company_id' => $this->company_id,
+        ]);
+    }
+}
\ No newline at end of file
diff --git a/app/assets/utils/classes/WarehouseManager.php b/app/assets/utils/classes/WarehouseManager.php
index e06656b..76ff906 100644
--- a/app/assets/utils/classes/WarehouseManager.php
+++ b/app/assets/utils/classes/WarehouseManager.php
@@ -125,8 +125,22 @@ class WarehouseManager {
      */
     public function syncRacks(int $storage_id, array $range): void {
 
+        // Guard: refuse if any rack under this storage_id is still occupied
         $this->validateRangeChange($storage_id, $range);
-        $this->removeRacksOutsideRange($storage_id, $range);
+
+        // Wipe all empty racks belonging to this storage_id
+        $sql = "DELETE FROM md_rack
+                WHERE company_id = :company_id
+                AND storage_id = :storage_id
+                AND product_sku IS NULL";
+
+        $sth = $this->pdo->prepare($sql);
+        $sth->execute([
+            ':company_id' => $this->company_id,
+            ':storage_id' => $storage_id,
+        ]);
+
+        // Reinsert the full range fresh
         $this->insertRacksInRange($storage_id, $range);
     }
 
@@ -161,32 +175,6 @@ class WarehouseManager {
         }
     }
 
-    /**
-     * Delete empty racks that fall outside the new range.
-     */
-    private function removeRacksOutsideRange(int $storage_id, array $range): void {
-
-        $sql = "DELETE FROM md_rack
-                WHERE company_id = :company_id 
-                  AND storage_id = :storage_id
-                  AND (
-                    CAST(aisle AS UNSIGNED) < :aisle_from OR 
-                    CAST(aisle AS UNSIGNED) > :aisle_to OR
-                    CAST(rack  AS UNSIGNED) < :rack_from OR 
-                    CAST(rack  AS UNSIGNED) > :rack_to
-                  )";
-
-        $sth = $this->pdo->prepare($sql);
-        $sth->execute([
-            ":company_id" => $this->company_id,
-            ":storage_id" => $storage_id,
-            ":aisle_from" => (int) $range['aisle_from'],
-            ":aisle_to"   => (int) $range['aisle_to'],
-            ":rack_from"  => (int) $range['rack_from'],
-            ":rack_to"    => (int) $range['rack_to'],
-        ]);
-    }
-
     /**
      * Insert rack rows for the full range (IGNORE skips duplicates).
      */
@@ -266,24 +254,30 @@ class WarehouseManager {
     // ─────────────────────────────────────────────────────────────
 
     /**
-     * Build a log JSON by appending an action entry to an existing md_rack.log.
-     * Entry captures user_id, dt (now), and login (session start) for audit context,
+     * Insert a log entry into md_rack_log for the given rack and action.
+     * Captures user_id, dt (now), and login (session start) for audit context,
      * plus any action-specific fields passed via $extra.
      */
-    private function buildRackLog(?string $existing_log, string $action, array $extra = []): string {
+    private function insertRackLog(int $rack_id, string $action, array $extra = []): void {
 
-        $log = json_decode($existing_log ?: '[]', true) ?: [];
+        $sql = "INSERT INTO md_rack_log
+                    (company_id, md_rack_id, user_id, dt, login, action, product_sku, td_stock_id)
+                VALUES
+                    (:company_id, :md_rack_id, :user_id, :dt, :login, :action, :product_sku, :td_stock_id)";
 
-        $log[] = array_merge([
-            'user_id' => $_SESSION['login_user_id'] ?? null,
-            'dt'      => date('Y-m-d H:i:s'),
-            'login'   => isset($_SESSION['otpTime']) 
-                         ? date('Y-m-d H:i:s', $_SESSION['otpTime']) 
-                         : null,
-            'action'  => $action,
-        ], $extra);
-
-        return json_encode($log, JSON_UNESCAPED_UNICODE);
+        $sth = $this->pdo->prepare($sql);
+        $sth->execute([
+            ':company_id'  => $this->company_id,
+            ':md_rack_id'  => $rack_id,
+            ':user_id'     => $_SESSION['login_user_id'] ?? null,
+            ':dt'          => date('Y-m-d H:i:s'),
+            ':login'       => isset($_SESSION['otpTime'])
+                            ? date('Y-m-d H:i:s', $_SESSION['otpTime'])
+                            : null,
+            ':action'      => $action,
+            ':product_sku' => $extra['product_sku'] ?? null,
+            ':td_stock_id' => $extra['td_stock_id'] ?? null,
+        ]);
     }
 
     /**
@@ -296,8 +290,8 @@ class WarehouseManager {
      */
     public function occupyRack($warehouse_id, $zone, $aisle, $rack, $product_sku, $td_stock_id): void {
 
-        // Lock and fetch current state (including log for in-place append)
-        $sql = "SELECT id, product_sku, `log` FROM md_rack
+
+        $sql = "SELECT id, product_sku FROM md_rack
                 WHERE company_id = :company_id 
                   AND warehouse = :warehouse
                   AND zone = :zone
@@ -328,20 +322,20 @@ class WarehouseManager {
         // Single atomic UPDATE: state + log together
         $sql = "UPDATE md_rack 
                 SET product_sku = :product_sku,
-                    td_stock_id = :td_stock_id,
-                    `log`       = :log
+                    td_stock_id = :td_stock_id
                 WHERE id = :id";
 
         $sth = $this->pdo->prepare($sql);
         $sth->execute([
             ":product_sku" => $product_sku,
             ":td_stock_id" => $td_stock_id,
-            ":log"         => $this->buildRackLog($current['log'], 'occupy', [
-                'product_sku' => $product_sku,
-                'td_stock_id' => $td_stock_id,
-            ]),
             ":id"          => $current['id'],
         ]);
+
+        $this->insertRackLog($current['id'], 'occupy', [
+            'product_sku' => $product_sku,
+            'td_stock_id' => $td_stock_id,
+        ]);
     }
 
     /**
@@ -349,8 +343,8 @@ class WarehouseManager {
      */
     public function releaseRack($warehouse_id, $zone, $aisle, $rack): void {
 
-        // Fetch current state + log (needed to append release event)
-        $sql = "SELECT id, product_sku, td_stock_id, `log` FROM md_rack
+
+        $sql = "SELECT id, product_sku, td_stock_id FROM md_rack
                 WHERE company_id = :company_id 
                   AND warehouse = :warehouse
                   AND zone = :zone
@@ -376,18 +370,18 @@ class WarehouseManager {
         // Clear state + record log in one UPDATE
         $sql = "UPDATE md_rack 
                 SET product_sku = NULL,
-                    td_stock_id = NULL,
-                    `log`       = :log
+                    td_stock_id = NULL
                 WHERE id = :id";
 
         $sth = $this->pdo->prepare($sql);
         $sth->execute([
-            ":log" => $this->buildRackLog($current['log'], 'release', [
-                'product_sku' => $current['product_sku'],
-                'td_stock_id' => $current['td_stock_id'],
-            ]),
             ":id"  => $current['id'],
         ]);
+
+        $this->insertRackLog($current['id'], 'release', [
+            'product_sku' => $current['product_sku'],
+            'td_stock_id' => $current['td_stock_id'],
+        ]);
     }
 
     /**
@@ -403,7 +397,7 @@ class WarehouseManager {
     ): void {
 
         // Fetch both racks with FOR UPDATE, ordered by id to prevent deadlocks
-        $sql = "SELECT id, warehouse, zone, aisle, rack, product_sku, td_stock_id, `log`
+        $sql = "SELECT id, warehouse, zone, aisle, rack, product_sku, td_stock_id
                 FROM md_rack
                 WHERE company_id = :company_id
                   AND (
@@ -464,32 +458,443 @@ class WarehouseManager {
 
         // Clear source — state + log in one UPDATE
         $sql = "UPDATE md_rack 
-                SET product_sku = NULL, td_stock_id = NULL, `log` = :log 
+                SET product_sku = NULL, td_stock_id = NULL
                 WHERE id = :id";
         $this->pdo->prepare($sql)->execute([
-            ":log" => $this->buildRackLog($from['log'], 'transfer_out', [
-                'product_sku' => $sku,
-                'td_stock_id' => $td_stock_id,
-                'to_rack_id'  => $to['id'],
-            ]),
             ":id"  => $from['id'],
         ]);
 
+        $this->insertRackLog($from['id'], 'transfer_out', [
+            'product_sku' => $sku,
+            'td_stock_id' => $td_stock_id,
+        ]);
+
         // Populate destination — state + log in one UPDATE
         $sql = "UPDATE md_rack 
-                SET product_sku = :sku, td_stock_id = :td_stock_id, `log` = :log 
+                SET product_sku = :sku, td_stock_id = :td_stock_id
                 WHERE id = :id";
         $this->pdo->prepare($sql)->execute([
             ":sku"         => $sku,
             ":td_stock_id" => $td_stock_id,
-            ":log"         => $this->buildRackLog($to['log'], 'transfer_in', [
-                'product_sku'  => $sku,
-                'td_stock_id'  => $td_stock_id,
-                'from_rack_id' => $from['id'],
-            ]),
             ":id"          => $to['id'],
         ]);
+
+        $this->insertRackLog($to['id'], 'transfer_in', [
+            'product_sku' => $sku,
+            'td_stock_id' => $td_stock_id,
+        ]);
     }
+
+
+    // ─────────────────────────────────────────────────────────────
+    // Delete (soft-delete) operations
+    // ─────────────────────────────────────────────────────────────
+
+    /**
+     * Validate that a given row is the latest transaction for its SKU in the table.
+     * Throws a descriptive exception if a newer transaction exists.
+     *
+     * @param string $product_sku  SKU to check
+     * @param string $row_date     The date of the row being deleted
+     * @param string $product_name Human-readable product name for error message
+     * @throws Exception if a newer transaction exists
+     */
+    private function validateLatestTransaction(
+        string $product_sku,
+        string $row_date,
+        string $product_name
+    ): void {
+
+        // Discover all td_stock_* tables for this database
+        $sth = $this->pdo->prepare(
+            "SELECT table_name FROM information_schema.tables
+            WHERE table_schema = DATABASE()
+            AND table_name LIKE 'td_stock_%'"
+        );
+        $sth->execute();
+        $tables = $sth->fetchAll(PDO::FETCH_COLUMN);
+
+        if (empty($tables)) {
+            return;
+        }
+
+        // Build UNION across all td_stock_* tables to find global MAX(date)
+        $unions = implode(' UNION ALL ', array_map(
+            fn($t) => "SELECT `type`, `date` FROM `$t`
+                    WHERE company_id = :company_id
+                        AND product_sku = :product_sku",
+            $tables
+        ));
+
+        $sth = $this->pdo->prepare(
+            "SELECT `type`, `date` FROM ($unions) AS all_stock
+            ORDER BY `date` DESC
+            LIMIT 1"
+        );
+        $sth->execute([
+            ':company_id'  => $this->company_id,
+            ':product_sku' => $product_sku,
+        ]);
+        $latest = $sth->fetch(PDO::FETCH_ASSOC);
+
+        if (!$latest || $row_date === $latest['date']) {
+            return; // ✓ this is the latest globally — allow
+        }
+
+        $type = strtoupper($latest['type']);
+        $date = $latest['date'];
+
+        throw new Exception(
+            "Cannot delete — \"{$product_name}\" has a newer " .
+            "{$type} transaction on {$date} that must be deleted first."
+        );
+    }
+
+    /**
+     * Helper to build a log entry with consistent user and timestamp info for warehouse operations.
+     */
+    private function buildLogEntry(string $action): array {
+        return [
+            'user_id' => $_SESSION['login_user_id'] ?? null,
+            'dt'      => date('Y-m-d H:i:s'),
+            'login'   => isset($_SESSION['otpTime'])
+                        ? date('Y-m-d H:i:s', $_SESSION['otpTime'])
+                        : null,
+            'action'  => $action,
+        ];
+    }
+
+    /**
+     * Resolve product name from md_product for readable error messages.
+     */
+    private function getProductName(string $product_sku): string {
+
+        $sth = $this->pdo->prepare(
+            "SELECT product_name FROM md_product
+             WHERE company_id = :company_id AND sku = :sku"
+        );
+        $sth->execute([
+            ':company_id' => $this->company_id,
+            ':sku'        => $product_sku,
+        ]);
+        return $sth->fetchColumn() ?: $product_sku;
+    }
+
+    /**
+     * Soft-delete a stock_in record and reverse its side effects.
+     *
+     * - Validates this is the latest transaction for the SKU
+     * - Negates company_id (soft-delete)
+     * - Releases the rack
+     * - Reverses the balance
+     *
+     * Must be called inside a DB transaction by the caller.
+     *
+     * @throws Exception if not the latest transaction or record not found
+     */
+    public function deleteStockIn(int $stock_id, int $warehouse_id): void {
+
+        $ctx   = $this->getStockContext($warehouse_id, $stock_id);
+        $table = $ctx['table'];
+        $row   = $ctx['row'];
+
+        if (!$row) {
+            throw new Exception("Stock in record not found.");
+        }
+
+        $product_sku  = $row['product_sku'];
+        $product_name = $this->getProductName($product_sku);
+
+        $this->validateLatestTransaction($product_sku, $row['date'], $product_name);
+
+        // Soft-delete
+        $this->pdo->prepare(
+            "UPDATE `$table`
+            SET company_id = company_id * -1
+            WHERE id = :id AND company_id = :company_id"
+        )->execute([':id' => $stock_id, ':company_id' => $this->company_id]);
+
+        // Release the rack
+        $this->releaseRack($warehouse_id, $row['zone'], $row['aisle'], $row['rack']);
+
+        // Reverse balance
+        $this->adjustBalance('in', $warehouse_id, $product_sku, (int)$row['in'], 0);
+    }
+
+    /**
+     * Soft-delete a stock_out record and reverse its side effects.
+     *
+     * - Validates this is the latest transaction for the SKU
+     * - Negates company_id (soft-delete)
+     * - Re-occupies the rack with the original stock_in batch (via ref_id)
+     * - Reverses the balance
+     *
+     * Must be called inside a DB transaction by the caller.
+     *
+     * @throws Exception if not the latest transaction or record not found
+     */
+    public function deleteStockOut(int $stock_id, int $warehouse_id): void {
+
+        $ctx   = $this->getStockContext($warehouse_id, $stock_id);
+        $table = $ctx['table'];
+        $row   = $ctx['row'];
+
+        if (!$row) {
+            throw new Exception("Stock out record not found.");
+        }
+
+        $product_sku  = $row['product_sku'];
+        $product_name = $this->getProductName($product_sku);
+
+        $this->validateLatestTransaction($product_sku, $row['date'], $product_name);
+
+        // Soft-delete
+        $this->pdo->prepare(
+            "UPDATE `$table`
+            SET company_id = company_id * -1
+            WHERE id = :id AND company_id = :company_id"
+        )->execute([':id' => $stock_id, ':company_id' => $this->company_id]);
+
+        // Re-occupy the rack — restore the stock_in batch that was consumed
+        $this->occupyRack(
+            $warehouse_id,
+            $row['zone'], $row['aisle'], $row['rack'],
+            $product_sku,
+            (int)$row['ref_id']
+        );
+
+        // Reverse balance
+        $this->adjustBalance('out', $warehouse_id, $product_sku, (int)$row['out'], 0);
+    }
+
+    /**
+     * Soft-delete a transfer record pair and reverse all side effects.
+     *
+     * - Validates this is the latest transaction for the SKU on BOTH warehouses
+     * - Negates company_id on both rows (soft-delete)
+     * - Releases destination rack, re-occupies source rack
+     * - Reverses balances on both warehouses
+     *
+     * Must be called inside a DB transaction by the caller.
+     *
+     * @throws Exception if not the latest transaction on either side, or records not found
+     */
+    public function deleteTransfer(int $from_stock_id, int $from_warehouse_id): void {
+
+        // Fetch the "from" row (transfer_out side)
+        $from_ctx   = $this->getStockContext($from_warehouse_id, $from_stock_id);
+        $from_table = $from_ctx['table'];
+        $from_row   = $from_ctx['row'];
+
+        if (!$from_row || $from_row['type'] !== 'transfer') {
+            throw new Exception("Transfer record not found.");
+        }
+
+        $product_sku  = $from_row['product_sku'];
+        $product_name = $this->getProductName($product_sku);
+        $to_warehouse = (int)$from_row['ref_warehouse'];
+        $ref_id       = (int)$from_row['ref_id'];
+
+        // Fetch the "to" row (transfer_in side)
+        $to_ctx = $this->getStockContext($to_warehouse, $ref_id);
+        $to_row = $to_ctx['row'];
+
+        if (!$to_row) {
+            throw new Exception("Paired destination record missing — data integrity issue.");
+        }
+
+        // Single global validation covers both warehouses
+        $this->validateLatestTransaction($product_sku, $from_row['date'], $product_name);
+
+        // Soft-delete both rows
+        $this->pdo->prepare(
+            "UPDATE `$from_table`
+            SET company_id = company_id * -1
+            WHERE id = :id AND company_id = :company_id"
+        )->execute([':id' => $from_stock_id, ':company_id' => $this->company_id]);
+
+        $this->pdo->prepare(
+            "UPDATE `{$to_ctx['table']}`
+            SET company_id = company_id * -1
+            WHERE id = :id AND company_id = :company_id"
+        )->execute([':id' => $ref_id, ':company_id' => $this->company_id]);
+
+        // Destination rack was occupied by transfer_in — release it
+        $this->releaseRack(
+            $to_warehouse,
+            $to_row['zone'], $to_row['aisle'], $to_row['rack']
+        );
+
+        // Source rack was released by transfer_out — re-occupy with original batch
+        $this->occupyRack(
+            $from_warehouse_id,
+            $from_row['zone'], $from_row['aisle'], $from_row['rack'],
+            $product_sku,
+            $from_stock_id
+        );
+
+        // Reverse balances
+        $quantity = (int)$from_row['out'];
+        $this->adjustBalance('out', $from_warehouse_id, $product_sku, $quantity, 0);
+        $this->adjustBalance('in',  $to_warehouse,      $product_sku, $quantity, 0);
+    }
+
+    /**
+     * Soft-delete a warehouse.
+     *
+     * Blocks if any md_storage references this warehouse by name.
+     *
+     * Must be called inside a DB transaction by the caller.
+     *
+     * @throws Exception if warehouse not found or has dependent storage
+     */
+    public function deleteWarehouse(int $warehouse_id): void {
+
+        $sth = $this->pdo->prepare(
+            "SELECT id, warehouse_name, `log` FROM md_warehouse
+            WHERE company_id = :company_id AND id = :id"
+        );
+        $sth->execute([
+            ':company_id' => $this->company_id,
+            ':id'         => $warehouse_id,
+        ]);
+        $row = $sth->fetch(PDO::FETCH_ASSOC);
+
+        if (!$row) {
+            throw new Exception("Warehouse not found.");
+        }
+
+        // Block if any md_storage references this warehouse by name
+        $sth = $this->pdo->prepare(
+            "SELECT COUNT(*) FROM md_storage
+            WHERE company_id = :company_id
+            AND warehouse = :warehouse_name"
+        );
+        $sth->execute([
+            ':company_id'     => $this->company_id,
+            ':warehouse_name' => $row['warehouse_name'],
+        ]);
+
+        if ($sth->fetchColumn() > 0) {
+            throw new Exception(
+                "Cannot delete — warehouse \"{$row['warehouse_name']}\" " .
+                "still has storage locations assigned to it."
+            );
+        }
+
+        // Append delete event to log
+        $log   = json_decode($row['log'] ?? '[]', true) ?: [];
+        $log[] = $this->buildLogEntry('delete');
+
+        // Soft-delete
+        $this->pdo->prepare(
+            "UPDATE md_warehouse
+            SET company_id = company_id * -1,
+                `log`      = :log
+            WHERE id = :id AND company_id = :company_id"
+        )->execute([
+            ':log'        => json_encode($log),
+            ':id'         => $warehouse_id,
+            ':company_id' => $this->company_id,
+        ]);
+    }
+
+
+    /**
+     * Soft-delete a storage record and its associated racks.
+     *
+     * - Blocks if any md_rack under this storage_id is occupied
+     * - Hard-deletes md_rack_log rows for those racks
+     * - Soft-deletes all md_rack rows under this storage_id
+     * - Soft-deletes md_storage
+     *
+     * Must be called inside a DB transaction by the caller.
+     *
+     * @throws Exception if storage not found or has occupied racks
+     */
+    public function deleteStorage(int $storage_id): void {
+
+        $sth = $this->pdo->prepare(
+            "SELECT id, zone, `log` FROM md_storage
+            WHERE company_id = :company_id AND id = :id"
+        );
+        $sth->execute([
+            ':company_id' => $this->company_id,
+            ':id'         => $storage_id,
+        ]);
+        $row = $sth->fetch(PDO::FETCH_ASSOC);
+
+        if (!$row) {
+            throw new Exception("Storage not found.");
+        }
+
+        // Block if any rack under this storage is occupied
+        $sth = $this->pdo->prepare(
+            "SELECT COUNT(*) FROM md_rack
+            WHERE company_id = :company_id
+            AND storage_id = :storage_id
+            AND product_sku IS NOT NULL"
+        );
+        $sth->execute([
+            ':company_id' => $this->company_id,
+            ':storage_id' => $storage_id,
+        ]);
+
+        if ($sth->fetchColumn() > 0) {
+            throw new Exception(
+                "Cannot delete — storage zone \"{$row['zone']}\" " .
+                "still has occupied racks with stock."
+            );
+        }
+
+        // Collect rack IDs before deleting — needed for rack log cleanup
+        $sth = $this->pdo->prepare(
+            "SELECT id FROM md_rack
+            WHERE company_id = :company_id
+            AND storage_id = :storage_id"
+        );
+        $sth->execute([
+            ':company_id' => $this->company_id,
+            ':storage_id' => $storage_id,
+        ]);
+        $rack_ids = $sth->fetchAll(PDO::FETCH_COLUMN);
+
+        // Hard-delete md_rack_log for these racks
+        if (!empty($rack_ids)) {
+            $placeholders = implode(',', array_fill(0, count($rack_ids), '?'));
+            $this->pdo->prepare(
+                "DELETE FROM md_rack_log WHERE md_rack_id IN ($placeholders)"
+            )->execute($rack_ids);
+        }
+
+        // Soft-delete all md_rack rows under this storage
+        $this->pdo->prepare(
+            "UPDATE md_rack
+            SET company_id = company_id * -1
+            WHERE company_id = :company_id
+            AND storage_id = :storage_id"
+        )->execute([
+            ':company_id' => $this->company_id,
+            ':storage_id' => $storage_id,
+        ]);
+
+        // Append delete event to log
+        $log   = json_decode($row['log'] ?? '[]', true) ?: [];
+        $log[] = $this->buildLogEntry('delete');
+
+        // Soft-delete md_storage
+        $this->pdo->prepare(
+            "UPDATE md_storage
+            SET company_id = company_id * -1,
+                `log`      = :log
+            WHERE id = :id AND company_id = :company_id"
+        )->execute([
+            ':log'        => json_encode($log),
+            ':id'         => $storage_id,
+            ':company_id' => $this->company_id,
+        ]);
+    }
+
 }
 
 ?>
\ No newline at end of file
diff --git a/app/contact/api/engine/remove_contact.php b/app/contact/api/engine/remove_contact.php
new file mode 100644
index 0000000..28dc3c9
--- /dev/null
+++ b/app/contact/api/engine/remove_contact.php
@@ -0,0 +1,29 @@
+<?php
+    session_start();
+    require '../../../assets/utils/db_auth.php';
+    require '../../../assets/utils/classes/ContactManager.php';
+
+    try {
+
+        dbTransaction($pdo2, function($pdo) use ($data, $company_id) {
+
+            $contactMgmt = new ContactManager($pdo, $company_id);
+            $contactMgmt->deleteContact((int)$data['id']);
+
+        });
+
+        $answer["success"] = 1;
+
+    } catch (PDOException $e) {
+        $answer["success"] = 0;
+        $answer["message"] = "Database error, please try again";
+        http_response_code(500);
+
+    } catch (Exception $e) {
+        $answer["success"] = 0;
+        $answer["message"] = $e->getMessage();
+        http_response_code(400);
+    }
+
+    exit(json_encode($answer));
+?>
\ No newline at end of file
diff --git a/app/contact/api/engine/remove_contact_type.php b/app/contact/api/engine/remove_contact_type.php
new file mode 100644
index 0000000..6e89e9e
--- /dev/null
+++ b/app/contact/api/engine/remove_contact_type.php
@@ -0,0 +1,29 @@
+<?php
+    session_start();
+    require '../../../assets/utils/db_auth.php';
+    require '../../../assets/utils/classes/ContactManager.php';
+
+    try {
+
+        dbTransaction($pdo2, function($pdo) use ($data, $company_id) {
+
+            $contactMgmt = new ContactManager($pdo, $company_id);
+            $contactMgmt->deleteContactType((int)$data['id']);
+
+        });
+
+        $answer["success"] = 1;
+
+    } catch (PDOException $e) {
+        $answer["success"] = 0;
+        $answer["message"] = "Database error, please try again";
+        http_response_code(500);
+
+    } catch (Exception $e) {
+        $answer["success"] = 0;
+        $answer["message"] = $e->getMessage();
+        http_response_code(400);
+    }
+
+    exit(json_encode($answer));
+?>
\ No newline at end of file
diff --git a/app/contact/contact.php b/app/contact/contact.php
index 7db527c..aebf043 100644
--- a/app/contact/contact.php
+++ b/app/contact/contact.php
@@ -268,7 +268,7 @@
             </td>
             <td class="py-3">
               <a href="<?php echo $server_url?>contact/manage_contact_type.php?id=${item['id']}" class=""><i class="ti ti-eye fs-5"></i></a>
-              <a href="#" class="link-danger"><i class="ti ti-trash ms-2 fs-5"></i></a>
+              <a href="javascript:;" class="link-danger" onclick="remove_contact_type(${item['id']},$(this))"><i class="ti ti-trash ms-2 fs-5"></i></a>
             </td>
           </tr>`;
     })
@@ -331,7 +331,7 @@
             </td>
             <td class="py-3">
               <a href="<?php echo $server_url?>contact/manage_contact.php?id=${item['id']}" class=""><i class="ti ti-eye fs-5"></i></a>
-              <a href="#" class="link-danger"><i class="ti ti-trash ms-2 fs-5"></i></a>
+              <a href="javascript:;" class="link-danger" onclick="remove_contact(${item['id']},$(this))"><i class="ti ti-trash ms-2 fs-5"></i></a>
             </td>
           </tr>`;
     })
@@ -340,6 +340,48 @@
 
   }
 
+
+  function remove_contact_type(id,element) {
+
+    return ajax_request({
+      url: "<?php echo $server_url?>contact/api/engine/remove_contact_type.php",
+      autoPrepare: true,
+      checkRequired: 0,
+      debugMode: 0,
+      data: {
+        id: id
+      },
+      action: 'delete',
+      onSuccess: function(res) {
+
+        element.parent().parent().remove();
+        
+      }
+    });
+
+  }
+
+
+  function remove_contact(id,element) {
+
+    return ajax_request({
+      url: "<?php echo $server_url?>contact/api/engine/remove_contact.php",
+      autoPrepare: true,
+      checkRequired: 0,
+      debugMode: 0,
+      data: {
+        id: id
+      },
+      action: 'delete',
+      onSuccess: function(res) {
+
+        element.parent().parent().remove();
+        
+      }
+    });
+
+  }
+
   $(async function() {
     try {
       await retrieve_contact_type();
diff --git a/app/ics/api/engine/delete_stock_in.php b/app/ics/api/engine/delete_stock_in.php
new file mode 100644
index 0000000..d4e2bbb
--- /dev/null
+++ b/app/ics/api/engine/delete_stock_in.php
@@ -0,0 +1,32 @@
+<?php
+    session_start();
+    require '../../../assets/utils/db_auth.php';
+    require '../../../assets/utils/classes/WarehouseManager.php';
+
+    try {
+
+        dbTransaction($pdo2, function($pdo) use ($data, $company_id) {
+
+            $whMgmt = new WarehouseManager($pdo, $company_id);
+            $whMgmt->deleteStockIn(
+                (int)$data['id'],
+                (int)$data['wh']
+            );
+
+        });
+
+        $answer["success"] = 1;
+
+    } catch (PDOException $e) {
+        $answer["success"] = 0;
+        $answer["message"] = "Database error, please try again";
+        http_response_code(500);
+
+    } catch (Exception $e) {
+        $answer["success"] = 0;
+        $answer["message"] = $e->getMessage();
+        http_response_code(400);
+    }
+
+    exit(json_encode($answer));
+?>
\ No newline at end of file
diff --git a/app/ics/api/engine/delete_stock_out.php b/app/ics/api/engine/delete_stock_out.php
new file mode 100644
index 0000000..2f19b97
--- /dev/null
+++ b/app/ics/api/engine/delete_stock_out.php
@@ -0,0 +1,32 @@
+<?php
+    session_start();
+    require '../../../assets/utils/db_auth.php';
+    require '../../../assets/utils/classes/WarehouseManager.php';
+
+    try {
+
+        dbTransaction($pdo2, function($pdo) use ($data, $company_id) {
+
+            $whMgmt = new WarehouseManager($pdo, $company_id);
+            $whMgmt->deleteStockOut(
+                (int)$data['id'],
+                (int)$data['wh']
+            );
+
+        });
+
+        $answer["success"] = 1;
+
+    } catch (PDOException $e) {
+        $answer["success"] = 0;
+        $answer["message"] = "Database error, please try again";
+        http_response_code(500);
+
+    } catch (Exception $e) {
+        $answer["success"] = 0;
+        $answer["message"] = $e->getMessage();
+        http_response_code(400);
+    }
+
+    exit(json_encode($answer));
+?>
\ No newline at end of file
diff --git a/app/ics/api/engine/delete_stock_transfer.php b/app/ics/api/engine/delete_stock_transfer.php
new file mode 100644
index 0000000..c211a84
--- /dev/null
+++ b/app/ics/api/engine/delete_stock_transfer.php
@@ -0,0 +1,32 @@
+<?php
+    session_start();
+    require '../../../assets/utils/db_auth.php';
+    require '../../../assets/utils/classes/WarehouseManager.php';
+
+    try {
+
+        dbTransaction($pdo2, function($pdo) use ($data, $company_id) {
+
+            $whMgmt = new WarehouseManager($pdo, $company_id);
+            $whMgmt->deleteTransfer(
+                (int)$data['id'],
+                (int)$data['wh']
+            );
+
+        });
+
+        $answer["success"] = 1;
+
+    } catch (PDOException $e) {
+        $answer["success"] = 0;
+        $answer["message"] = "Database error, please try again";
+        http_response_code(500);
+
+    } catch (Exception $e) {
+        $answer["success"] = 0;
+        $answer["message"] = $e->getMessage();
+        http_response_code(400);
+    }
+
+    exit(json_encode($answer));
+?>
\ No newline at end of file
diff --git a/app/ics/api/engine/manage_stock_in.php b/app/ics/api/engine/manage_stock_in.php
index 4558a06..77564b3 100644
--- a/app/ics/api/engine/manage_stock_in.php
+++ b/app/ics/api/engine/manage_stock_in.php
@@ -24,11 +24,6 @@
 
                 // UPDATE existing stock_in record
                 $sql = "UPDATE `$table` SET
-                            `product_sku` = :product_sku,
-                            `in`          = :quantity,
-                            `zone`        = :zone,
-                            `aisle`       = :aisle,
-                            `rack`        = :rack,
                             `contact_id`  = :contact_id,
                             `description` = :description,
                             `log`         = :log
@@ -38,41 +33,12 @@
                 $sth->execute([
                     ":id"          => $id,
                     ":company_id"  => $company_id,
-                    ":product_sku" => $data["product_sku"],
-                    ":quantity"    => $data["quantity"],
-                    ":zone"        => $data["zone"],
-                    ":aisle"       => $data["aisle"],
-                    ":rack"        => $data["rack"],
                     ":contact_id"  => (int)$data["contact_id"],
                     ":description" => $data["description"],
                     ":log"         => json_encode($table_log),
                 ]);
 
-                // On UPDATE, td_stock_id stays the same (this record's ID)
-                $td_stock_id = $id;
 
-                // Only touch md_rack if the physical location actually changed.
-                // Skipping when unchanged avoids redundant log entries and release/occupy cycles.
-                $rack_changed = (
-                    ($row['zone']  ?? '') != $data['zone']  ||
-                    ($row['aisle'] ?? '') != $data['aisle'] ||
-                    ($row['rack']  ?? '') != $data['rack']
-                );
-
-                if ($rack_changed) {
-                    // Free up the old rack
-                    $whMgmt->releaseRack(
-                        $warehouse_id,
-                        $row['zone'], $row['aisle'], $row['rack']
-                    );
-                    // Claim the new rack, linked to the same stock record
-                    $whMgmt->occupyRack(
-                        $warehouse_id,
-                        $data['zone'], $data['aisle'], $data['rack'],
-                        $data['product_sku'],
-                        $td_stock_id
-                    );
-                }
 
             } else {
 
@@ -107,17 +73,17 @@
                     $data['product_sku'],
                     $td_stock_id
                 );
-            }
+                // Balance adjustment handles both INSERT (delta = full qty) 
+                // and UPDATE (delta = new - old) via the same formula.
+                $whMgmt->adjustBalance(
+                    'in', 
+                    $warehouse_id, 
+                    $data["product_sku"], 
+                    $row['in'] ?? 0, 
+                    $data["quantity"]
+                );
 
-            // Balance adjustment handles both INSERT (delta = full qty) 
-            // and UPDATE (delta = new - old) via the same formula.
-            $whMgmt->adjustBalance(
-                'in', 
-                $warehouse_id, 
-                $data["product_sku"], 
-                $row['in'] ?? 0, 
-                $data["quantity"]
-            );
+            }
 
         });
 
diff --git a/app/ics/api/engine/manage_stock_out.php b/app/ics/api/engine/manage_stock_out.php
index b8e4d68..705ca13 100644
--- a/app/ics/api/engine/manage_stock_out.php
+++ b/app/ics/api/engine/manage_stock_out.php
@@ -19,42 +19,10 @@
             $table_log = json_decode($row['log'] ?? '[]', true);
             $table_log[] = $logging;
 
-            // Look up the source stock record via the rack.
-            // Under 1:1, the rack points to exactly one td_stock_<wh> row.
-            $source_stock = $whMgmt->getRackStock(
-                $warehouse_id, 
-                $data["zone"], 
-                $data["aisle"], 
-                $data["rack"]
-            );
-
-            if (!$source_stock) {
-                throw new Exception(
-                    "Rack {$data['zone']}-{$data['aisle']}-{$data['rack']} is empty — nothing to take out."
-                );
-            }
-
-            // Defensive check — UI cascade should already prevent mismatches
-            if ($source_stock['product_sku'] !== $data["product_sku"]) {
-                throw new Exception(
-                    "Rack holds {$source_stock['product_sku']}, not {$data['product_sku']}."
-                );
-            }
-
-            // Quantity comes from the source stock_in row, NOT user input.
-            // Under 1:1, taking from this rack = taking the full batch.
-            $quantity = (int) $source_stock['in'];
-            $ref_id   = (int) $source_stock['id'];
-
             if ($id > 0) {
 
                 // UPDATE existing stock_out record
                 $sql = "UPDATE `$table` SET
-                            `product_sku` = :product_sku,
-                            `out`         = :quantity,
-                            `zone`        = :zone,
-                            `aisle`       = :aisle,
-                            `rack`        = :rack,
                             `contact_id`  = :contact_id,
                             `description` = :description,
                             `log`         = :log
@@ -64,41 +32,39 @@
                 $sth->execute([
                     ":id"          => $id,
                     ":company_id"  => $company_id,
-                    ":product_sku" => $data["product_sku"],
-                    ":quantity"    => $quantity,
-                    ":zone"        => $data["zone"],
-                    ":aisle"       => $data["aisle"],
-                    ":rack"        => $data["rack"],
                     ":contact_id"  => (int)$data["contact_id"],
                     ":description" => $data["description"],
                     ":log"         => json_encode($table_log),
                 ]);
 
-                // Only touch md_rack if the physical location actually changed.
-                $rack_changed = (
-                    ($row['zone']  ?? '') != $data['zone']  ||
-                    ($row['aisle'] ?? '') != $data['aisle'] ||
-                    ($row['rack']  ?? '') != $data['rack']
+            } else {
+
+                // Look up the source stock record via the rack.
+                // Under 1:1, the rack points to exactly one td_stock_<wh> row.
+                $source_stock = $whMgmt->getRackStock(
+                    $warehouse_id, 
+                    $data["zone"], 
+                    $data["aisle"], 
+                    $data["rack"]
                 );
 
-                if ($rack_changed) {
-                    // Re-occupy the old rack with the batch it originally held
-                    // (logically: the stock goes back to where it came from)
-                    $whMgmt->occupyRack(
-                        $warehouse_id,
-                        $row['zone'], $row['aisle'], $row['rack'],
-                        $row['product_sku'],
-                        $row['ref_id'] ?? null
-                    );
-
-                    // Release the new rack (the real stock-out action)
-                    $whMgmt->releaseRack(
-                        $warehouse_id,
-                        $data['zone'], $data['aisle'], $data['rack']
+                if (!$source_stock) {
+                    throw new Exception(
+                        "Rack {$data['zone']}-{$data['aisle']}-{$data['rack']} is empty — nothing to take out."
                     );
                 }
 
-            } else {
+                // Defensive check — UI cascade should already prevent mismatches
+                if ($source_stock['product_sku'] !== $data["product_sku"]) {
+                    throw new Exception(
+                        "Rack holds {$source_stock['product_sku']}, not {$data['product_sku']}."
+                    );
+                }
+
+                // Quantity comes from the source stock_in row, NOT user input.
+                // Under 1:1, taking from this rack = taking the full batch.
+                $quantity = (int) $source_stock['in'];
+                $ref_id   = (int) $source_stock['id'];
 
                 // INSERT new stock_out record.
                 // ref_id links this stock_out row back to the stock_in batch it consumed.
@@ -130,18 +96,18 @@
                     $warehouse_id, 
                     $data["zone"], $data["aisle"], $data["rack"]
                 );
-            }
+                // Balance: total_out increases by delta.
+                //   INSERT: $row['out'] = 0   → delta = full quantity
+                //   UPDATE: $row['out'] = old → delta = new - old
+                $whMgmt->adjustBalance(
+                    'out', 
+                    $warehouse_id, 
+                    $data["product_sku"], 
+                    $row['out'] ?? 0, 
+                    $quantity
+                );
 
-            // Balance: total_out increases by delta.
-            //   INSERT: $row['out'] = 0   → delta = full quantity
-            //   UPDATE: $row['out'] = old → delta = new - old
-            $whMgmt->adjustBalance(
-                'out', 
-                $warehouse_id, 
-                $data["product_sku"], 
-                $row['out'] ?? 0, 
-                $quantity
-            );
+            }
 
         });
 
diff --git a/app/ics/api/engine/retrieve_stock_in.php b/app/ics/api/engine/retrieve_stock_in.php
index b2add0f..c66cf06 100644
--- a/app/ics/api/engine/retrieve_stock_in.php
+++ b/app/ics/api/engine/retrieve_stock_in.php
@@ -31,7 +31,7 @@
           a.company_id = b.company_id and 
           a.contact_id = b.id
         LEFT JOIN md_product c ON
-          a.company_id = b.company_id and 
+          a.company_id = c.company_id and 
           a.product_sku = c.sku
         WHERE 
             a.company_id = :company_id and 
diff --git a/app/ics/api/engine/retrieve_stock_out.php b/app/ics/api/engine/retrieve_stock_out.php
index 40e359d..68b43b5 100644
--- a/app/ics/api/engine/retrieve_stock_out.php
+++ b/app/ics/api/engine/retrieve_stock_out.php
@@ -31,7 +31,7 @@
           a.company_id = b.company_id and 
           a.contact_id = b.id
         LEFT JOIN md_product c ON
-          a.company_id = b.company_id and 
+          a.company_id = c.company_id and 
           a.product_sku = c.sku
         WHERE 
             a.company_id = :company_id and 
diff --git a/app/ics/manage_stock_in.php b/app/ics/manage_stock_in.php
index 8425248..35f210e 100644
--- a/app/ics/manage_stock_in.php
+++ b/app/ics/manage_stock_in.php
@@ -273,6 +273,8 @@
               $('#product_name').val(data.product_name);
               $('#product_sku').attr('secondary', data.product_sku);
 
+              $('#product_sku,#quantity').prop('disabled', true);
+
               $(`button[type=submit]`).text('Update');
               $(`button[type=reset]`).hide();
 
diff --git a/app/ics/manage_stock_out.php b/app/ics/manage_stock_out.php
index 40383b7..8f6293b 100644
--- a/app/ics/manage_stock_out.php
+++ b/app/ics/manage_stock_out.php
@@ -271,6 +271,8 @@
               $('#product_name').val(data.product_name);
               $('#product_sku').attr('secondary', data.product_sku);
 
+              $('#product_sku,#quantity').prop('disabled', true);
+
               $(`button[type=submit]`).text('Update');
               $(`button[type=reset]`).hide();
 
diff --git a/app/ics/manage_stock_transfer.php b/app/ics/manage_stock_transfer.php
index 4e4ed1d..1376d8d 100644
--- a/app/ics/manage_stock_transfer.php
+++ b/app/ics/manage_stock_transfer.php
@@ -344,10 +344,12 @@
         $('#contact').val(data.contact_name)
           .attr('secondary', data.contact_name)
           .attr('data-id', data.contact_id);
-        console.log(data);
+
         $('#product_name').val(data.product_name);
         $('#product_sku').attr('secondary', data.product_sku);
 
+        $('#product_sku,#quantity').prop('disabled', true);
+
         $(`button[type=submit]`).text('Update');
         $(`button[type=reset]`).hide();
 
diff --git a/app/ics/stock_in.php b/app/ics/stock_in.php
index 34fc53f..0e3c27a 100644
--- a/app/ics/stock_in.php
+++ b/app/ics/stock_in.php
@@ -133,7 +133,10 @@
             </td>
             <td class="py-3">
               <a href="<?php echo $server_url?>ics/manage_stock_in.php?id=${item['id']}&wh=${warehouse}" class=""><i class="ti ti-eye fs-5"></i></a>
-              <a href="#" class="link-danger"><i class="ti ti-trash ms-2 fs-5"></i></a>
+              <a href="javascript:void(0);" class="link-danger" 
+                onclick="delete_stock_in($(this),${item['id']})">
+                <i class="ti ti-trash ms-2 fs-5"></i>
+              </a>
             </td>
           </tr>`;
     })
@@ -162,6 +165,24 @@
 
   }
 
+  function delete_stock_in(element, id) {
+
+    return ajax_request({
+      url: "<?php echo $server_url?>ics/api/engine/delete_stock_in.php",
+      autoPrepare: true,
+      checkRequired: 0,
+      action: 'delete',
+      data : {
+        id: id,
+        wh: $(`select#warehouse`).val()
+       },
+      onSuccess: function(res) {
+        element.closest('tr').remove();
+      }
+    });
+
+  }
+
   $(async function() {
     try {
       await retrieve_warehouse();
diff --git a/app/ics/stock_out.php b/app/ics/stock_out.php
index 2883583..0c30699 100644
--- a/app/ics/stock_out.php
+++ b/app/ics/stock_out.php
@@ -133,7 +133,10 @@
             </td>
             <td class="py-3">
               <a href="<?php echo $server_url?>ics/manage_stock_out.php?id=${item['id']}&wh=${warehouse}" class=""><i class="ti ti-eye fs-5"></i></a>
-              <a href="#" class="link-danger"><i class="ti ti-trash ms-2 fs-5"></i></a>
+              <a href="javascript:void(0);" class="link-danger" 
+                onclick="delete_stock_out($(this),${item['id']})">
+                <i class="ti ti-trash ms-2 fs-5"></i>
+              </a>
             </td>
           </tr>`;
     })
@@ -162,6 +165,24 @@
 
   }
 
+  function delete_stock_out(element, id) {
+
+    return ajax_request({
+      url: "<?php echo $server_url?>ics/api/engine/delete_stock_out.php",
+      autoPrepare: true,
+      checkRequired: 0,
+      action: 'delete',
+      data : {
+        id: id,
+        wh: $(`select#warehouse`).val()
+       },
+      onSuccess: function(res) {
+        element.closest('tr').remove();
+      }
+    });
+
+  }
+
   $(async function() {
     try {
       await retrieve_warehouse();
diff --git a/app/ics/stock_transfer.php b/app/ics/stock_transfer.php
index 9a6a685..c1b3458 100644
--- a/app/ics/stock_transfer.php
+++ b/app/ics/stock_transfer.php
@@ -133,7 +133,10 @@
             </td>
             <td class="py-3">
               <a href="<?php echo $server_url?>ics/manage_stock_transfer.php?id=${item['id']}&wh=${warehouse}" class=""><i class="ti ti-eye fs-5"></i></a>
-              <a href="#" class="link-danger"><i class="ti ti-trash ms-2 fs-5"></i></a>
+              <a href="javascript:void(0);" class="link-danger" 
+                onclick="delete_stock_transfer($(this),${item['id']})">
+                <i class="ti ti-trash ms-2 fs-5"></i>
+              </a>
             </td>
           </tr>`;
     })
@@ -162,6 +165,26 @@
 
   }
 
+
+
+  function delete_stock_transfer(element, id) {
+
+    return ajax_request({
+      url: "<?php echo $server_url?>ics/api/engine/delete_stock_transfer.php",
+      autoPrepare: true,
+      checkRequired: 0,
+      action: 'delete',
+      data : {
+        id: id,
+        wh: $(`select#warehouse`).val()
+       },
+      onSuccess: function(res) {
+        element.closest('tr').remove();
+      }
+    });
+
+  }
+
   $(async function() {
     try {
       await retrieve_warehouse();
diff --git a/app/inventory/api/engine/remove_category.php b/app/inventory/api/engine/remove_category.php
index 0ed6092..27cf4c5 100644
--- a/app/inventory/api/engine/remove_category.php
+++ b/app/inventory/api/engine/remove_category.php
@@ -1,69 +1,18 @@
-<?php 
+<?php
     session_start();
     require '../../../assets/utils/db_auth.php';
+    require '../../../assets/utils/classes/ProductManager.php';
 
     try {
-        $result = dbTransaction($pdo2, function($pdo) use ($data, $company_id, $logging) {
 
-            $id = (int)($data['id'] ?? 0);
+        dbTransaction($pdo2, function($pdo) use ($data, $company_id) {
 
-            if ($id <= 0) {
-                throw new Exception("Invalid category ID.");
-            }
+            $productMgmt = new ProductManager($pdo, $company_id);
+            $productMgmt->deleteCategory((int)$data['id']);
 
-            // 1. Validate: check if category is in use by any product
-            $sql = "SELECT COUNT(*) 
-                    FROM md_product 
-                    WHERE company_id = :company_id 
-                      AND category = :id";
-            $sth = $pdo->prepare($sql);
-            $sth->execute([
-                ":company_id" => $company_id,
-                ":id" => $id
-            ]);
-
-            $product_count = (int) $sth->fetchColumn();
-
-            if ($product_count > 0) {
-                throw new Exception("Cannot remove category. It is currently used by {$product_count} product(s).");
-            }
-
-            // 2. Append to log history
-            $sql = "SELECT `log` FROM md_product_category
-                    WHERE company_id = :company_id AND id = :id";
-            $sth = $pdo->prepare($sql);
-            $sth->execute([
-                ":company_id" => $company_id,
-                ":id" => $id
-            ]);
-
-            $table_log = json_decode($sth->fetchColumn() ?: '[]', true);
-            if (!is_array($table_log)) $table_log = [];
-            $table_log[] = $logging;
-
-            // 3. Soft-delete via sign flip
-            $sql = "UPDATE md_product_category
-                    SET company_id = company_id * (-1),
-                        `log` = :log
-                    WHERE company_id = :company_id 
-                      AND id = :id";
-            $sth = $pdo->prepare($sql);
-            $sth->execute([
-                ":company_id" => $company_id,
-                ":id"         => $id,
-                ":log"        => json_encode($table_log, JSON_UNESCAPED_UNICODE),
-            ]);
-
-            if ($sth->rowCount() === 0) {
-                throw new Exception("Category not found or already removed.");
-            }
-
-            return $id;
         });
 
         $answer["success"] = 1;
-        $answer["message"] = "Category removed successfully.";
-        $answer["id"]      = $result;
 
     } catch (PDOException $e) {
         $answer["success"] = 0;
diff --git a/app/inventory/api/engine/remove_product.php b/app/inventory/api/engine/remove_product.php
new file mode 100644
index 0000000..630337d
--- /dev/null
+++ b/app/inventory/api/engine/remove_product.php
@@ -0,0 +1,29 @@
+<?php
+    session_start();
+    require '../../../assets/utils/db_auth.php';
+    require '../../../assets/utils/classes/ProductManager.php';
+
+    try {
+
+        dbTransaction($pdo2, function($pdo) use ($data, $company_id) {
+
+            $productMgmt = new ProductManager($pdo, $company_id);
+            $productMgmt->deleteProduct((int)$data['id']);
+
+        });
+
+        $answer["success"] = 1;
+
+    } catch (PDOException $e) {
+        $answer["success"] = 0;
+        $answer["message"] = "Database error, please try again";
+        http_response_code(500);
+
+    } catch (Exception $e) {
+        $answer["success"] = 0;
+        $answer["message"] = $e->getMessage();
+        http_response_code(400);
+    }
+
+    exit(json_encode($answer));
+?>
\ No newline at end of file
diff --git a/app/inventory/api/engine/remove_storage.php b/app/inventory/api/engine/remove_storage.php
new file mode 100644
index 0000000..3e7f336
--- /dev/null
+++ b/app/inventory/api/engine/remove_storage.php
@@ -0,0 +1,29 @@
+<?php
+    session_start();
+    require '../../../assets/utils/db_auth.php';
+    require '../../../assets/utils/classes/WarehouseManager.php';
+
+    try {
+
+        dbTransaction($pdo2, function($pdo) use ($data, $company_id) {
+
+            $whMgmt = new WarehouseManager($pdo, $company_id);
+            $whMgmt->deleteStorage((int)$data['id']);
+
+        });
+
+        $answer["success"] = 1;
+
+    } catch (PDOException $e) {
+        $answer["success"] = 0;
+        $answer["message"] = "Database error, please try again";
+        http_response_code(500);
+
+    } catch (Exception $e) {
+        $answer["success"] = 0;
+        $answer["message"] = $e->getMessage();
+        http_response_code(400);
+    }
+
+    exit(json_encode($answer));
+?>
\ No newline at end of file
diff --git a/app/inventory/api/engine/remove_warehouse.php b/app/inventory/api/engine/remove_warehouse.php
new file mode 100644
index 0000000..4926d82
--- /dev/null
+++ b/app/inventory/api/engine/remove_warehouse.php
@@ -0,0 +1,29 @@
+<?php
+    session_start();
+    require '../../../assets/utils/db_auth.php';
+    require '../../../assets/utils/classes/WarehouseManager.php';
+
+    try {
+
+        dbTransaction($pdo2, function($pdo) use ($data, $company_id) {
+
+            $whMgmt = new WarehouseManager($pdo, $company_id);
+            $whMgmt->deleteWarehouse((int)$data['id']);
+
+        });
+
+        $answer["success"] = 1;
+
+    } catch (PDOException $e) {
+        $answer["success"] = 0;
+        $answer["message"] = "Database error, please try again";
+        http_response_code(500);
+
+    } catch (Exception $e) {
+        $answer["success"] = 0;
+        $answer["message"] = $e->getMessage();
+        http_response_code(400);
+    }
+
+    exit(json_encode($answer));
+?>
\ No newline at end of file
diff --git a/app/inventory/product.php b/app/inventory/product.php
index 68b2ea9..aae13d0 100644
--- a/app/inventory/product.php
+++ b/app/inventory/product.php
@@ -298,6 +298,28 @@
 
 
 
+  function remove_product(id,element) {
+
+    return ajax_request({
+      url: "<?php echo $server_url?>inventory/api/engine/remove_product.php",
+      autoPrepare: true,
+      checkRequired: 0,
+      debugMode: 0,
+      data: {
+        id: id
+      },
+      action: 'delete',
+      onSuccess: function(res) {
+
+        element.parent().parent().remove();
+        
+      }
+    });
+
+  }
+
+
+
   function change_page_category(page_num) {
 
     var offset = (page_num - 1) * prop_limit;
@@ -382,7 +404,7 @@
             </td>
             <td class="py-3">
               <a href="<?php echo $server_url?>inventory/manage_product.php?id=${item['id']}" class=""><i class="ti ti-eye fs-5"></i></a>
-              <a href="#" class="link-danger"><i class="ti ti-trash ms-2 fs-5"></i></a>
+              <a href="javascript:;" class="link-danger" onclick="remove_product(${item['id']},$(this))"><i class="ti ti-trash ms-2 fs-5"></i></a>
             </td>
           </tr>`;
     })
diff --git a/app/inventory/warehouse.php b/app/inventory/warehouse.php
index 666cdaa..58af3aa 100644
--- a/app/inventory/warehouse.php
+++ b/app/inventory/warehouse.php
@@ -335,7 +335,7 @@
             </td>
             <td class="py-3">
               <a href="<?php echo $server_url?>inventory/manage_warehouse.php?id=${item['id']}" class=""><i class="ti ti-eye fs-5"></i></a>
-              <a href="#" class="link-danger"><i class="ti ti-trash ms-2 fs-5"></i></a>
+              <a href="javascript:;" class="link-danger" onclick="remove_warehouse(${item['id']},$(this))"><i class="ti ti-trash ms-2 fs-5"></i></a>
             </td>
           </tr>`;
     })
@@ -393,7 +393,7 @@
             <td class="py-3"></td>
             <td class="py-3">
               <a href="<?php echo $server_url?>inventory/manage_storage.php?id=${item['id']}" class=""><i class="ti ti-eye fs-5"></i></a>
-              <a href="#" class="link-danger"><i class="ti ti-trash ms-2 fs-5"></i></a>
+              <a href="javascript:;" class="link-danger" onclick="remove_storage(${item['id']},$(this))"><i class="ti ti-trash ms-2 fs-5"></i></a>
             </td>
           </tr>`;
     })
@@ -402,6 +402,49 @@
 
   }
 
+
+  function remove_warehouse(id,element) {
+
+    return ajax_request({
+      url: "<?php echo $server_url?>inventory/api/engine/remove_warehouse.php",
+      autoPrepare: true,
+      checkRequired: 0,
+      debugMode: 0,
+      data: {
+        id: id
+      },
+      action: 'delete',
+      onSuccess: function(res) {
+
+        element.parent().parent().remove();
+        
+      }
+    });
+
+  }
+
+
+  function remove_storage(id,element) {
+
+    return ajax_request({
+      url: "<?php echo $server_url?>inventory/api/engine/remove_storage.php",
+      autoPrepare: true,
+      checkRequired: 0,
+      debugMode: 0,
+      data: {
+        id: id
+      },
+      action: 'delete',
+      onSuccess: function(res) {
+
+        element.parent().parent().remove();
+        
+      }
+    });
+
+  }
+
+
   $(async function() {
     try {
       await retrieve_stats();