diff --git a/source/packages/plg_system_mokosuiteauto/src/Helper/DealHelper.php b/source/packages/plg_system_mokosuiteauto/src/Helper/DealHelper.php
new file mode 100644
index 0000000..8cc0d92
--- /dev/null
+++ b/source/packages/plg_system_mokosuiteauto/src/Helper/DealHelper.php
@@ -0,0 +1,101 @@
+<?php
+namespace Moko\Plugin\System\MokoSuiteAuto\Helper;
+
+defined('_JEXEC') or die;
+
+use Joomla\CMS\Factory;
+use Joomla\Database\DatabaseInterface;
+
+/**
+ * Deal management — sales deals, gross profit, F&I products, deal jacket.
+ */
+class DealHelper
+{
+	/**
+	 * Create a new deal.
+	 */
+	public static function create(int $vehicleId, int $buyerContactId, int $salespersonId, float $salePrice): object
+	{
+		if ($salePrice <= 0) {
+			throw new \InvalidArgumentException('Sale price must be positive.');
+		}
+
+		$db = Factory::getContainer()->get(DatabaseInterface::class);
+
+		$deal = (object) [
+			'vehicle_id'      => $vehicleId,
+			'buyer_contact_id'=> $buyerContactId,
+			'salesperson_id'  => $salespersonId,
+			'sale_price'      => round($salePrice, 2),
+			'status'          => 'negotiating',
+			'created_at'      => Factory::getDate()->toSql(),
+		];
+
+		$db->insertObject('#__mokosuiteauto_deals', $deal, 'id');
+
+		return (object) ['success' => true, 'deal_id' => (int) $deal->id];
+	}
+
+	/**
+	 * Calculate gross profit for a deal.
+	 */
+	public static function getGrossProfit(int $dealId): object
+	{
+		$db = Factory::getContainer()->get(DatabaseInterface::class);
+
+		$db->setQuery($db->getQuery(true)
+			->select('d.sale_price, v.invoice_price, v.reconditioning_cost')
+			->select('COALESCE(ti.appraisal_value, 0) AS trade_allowance')
+			->from($db->quoteName('#__mokosuiteauto_deals', 'd'))
+			->join('INNER', $db->quoteName('#__mokosuiteauto_vehicles', 'v') . ' ON v.id = d.vehicle_id')
+			->join('LEFT', $db->quoteName('#__mokosuiteauto_trade_ins', 'ti') . ' ON ti.id = d.trade_in_id')
+			->where('d.id = ' . (int) $dealId));
+		$deal = $db->loadObject();
+
+		if (!$deal) {
+			return (object) ['success' => false, 'error' => 'Deal not found'];
+		}
+
+		$frontGross = (float) $deal->sale_price - (float) $deal->invoice_price
+			- (float) ($deal->reconditioning_cost ?? 0);
+
+		// F&I back-end gross
+		$db->setQuery($db->getQuery(true)
+			->select('COALESCE(SUM(profit), 0) AS fi_gross')
+			->from('#__mokosuiteauto_deal_fi_products')
+			->where('deal_id = ' . (int) $dealId));
+		$backGross = (float) $db->loadResult();
+
+		return (object) [
+			'deal_id'     => $dealId,
+			'sale_price'  => (float) $deal->sale_price,
+			'invoice'     => (float) $deal->invoice_price,
+			'recon_cost'  => (float) ($deal->reconditioning_cost ?? 0),
+			'front_gross' => round($frontGross, 2),
+			'back_gross'  => round($backGross, 2),
+			'total_gross' => round($frontGross + $backGross, 2),
+		];
+	}
+
+	/**
+	 * Get sales dashboard — deals by status, monthly volume.
+	 */
+	public static function getSalesDashboard(): object
+	{
+		$db = Factory::getContainer()->get(DatabaseInterface::class);
+
+		$db->setQuery($db->getQuery(true)
+			->select('COUNT(*) AS total_deals')
+			->select('SUM(CASE WHEN status = ' . $db->quote('delivered') . ' THEN 1 ELSE 0 END) AS delivered')
+			->select('SUM(CASE WHEN status = ' . $db->quote('negotiating') . ' THEN 1 ELSE 0 END) AS in_negotiation')
+			->select('SUM(CASE WHEN status = ' . $db->quote('pending_finance') . ' THEN 1 ELSE 0 END) AS pending_finance')
+			->select('SUM(CASE WHEN status = ' . $db->quote('delivered') . ' AND MONTH(delivered_at) = MONTH(NOW()) AND YEAR(delivered_at) = YEAR(NOW()) THEN sale_price ELSE 0 END) AS mtd_volume')
+			->select('SUM(CASE WHEN status = ' . $db->quote('delivered') . ' AND MONTH(delivered_at) = MONTH(NOW()) AND YEAR(delivered_at) = YEAR(NOW()) THEN 1 ELSE 0 END) AS mtd_units')
+			->from('#__mokosuiteauto_deals'));
+
+		$stats = $db->loadObject();
+		$stats->mtd_volume = round((float) ($stats->mtd_volume ?? 0), 0);
+
+		return $stats;
+	}
+}