docs: Add cost analysis section to pay-as-you-go transition guide

Author: MikeRayMSFT

docs/sql-server/azure-arc/manage-pay-as-you-go-transition.md

@@ -138,6 +138,58 @@ SQL Server enabled by Azure Arc automatically installs Azure extension for SQL S
 
 With a pay-as-you-go subscription, the health of the extensions becomes a critical factor of your compliance as it collects the usage data and ensures the correct billing. The intermittent disconnections up to 30 days are allowed as the extension maintains a usage log on the machine, but it is your responsibility to ensure the extensions stay healthy. The Azure portal includes a [Health Dashboard](https://ms.portal.azure.com/#view/Microsoft_Azure_ArcCenterUX/ArcCenterMenuBlade/~/sqlServerHealthDashboard) providing the high level view of the extensions' state. For details of troubleshooting of the unhealthy extensions, see [Troubleshoot Azure extension for SQL Server](troubleshoot-extension.md).
 
+## Analyze costs
+
+After you transition to pay-as-you-go billing, you can view current and forecasted charges through [Azure Cost Management](/azure/cost-management-billing/cost-management-billing-overview). Upcoming charges for Azure Arc-enabled SQL Server pay-as-you-go aren't shown on SQL Server or Arc resource pages. All cost analysis and forecasting happens at the subscription level or higher.
+
+### View forecasted charges
+
+To view forecasted pay-as-you-go charges:
+
+1. In the Azure portal, open **Cost Management** > **Cost analysis**.
+1. Select the appropriate scope (subscription, management group, or resource group).
+1. Confirm the chart shows both actual and forecasted costs.
+   - Solid bars or lines represent actual costs
+   - Shaded extensions represent forecasted costs based on historical usage trends
+1. Set the date range to the current month to see projected month-end costs.
+
+### Filter for Arc SQL pay-as-you-go costs
+
+To isolate Azure Arc-enabled SQL Server pay-as-you-go charges, apply these filters:
+
+| Filter | Value |
+|--------|-------|
+| **Service name** | Azure Arc-enabled SQL Server |
+| **Charge type** | Usage |
+| **Publisher type** | Microsoft |
+
+> [!TIP]
+> If **Azure Arc-enabled SQL Server** doesn't appear in the filter list, remove other filters first, then reapply **Service name**.
+
+### Identify resource-level costs
+
+To see which SQL Server instances are driving costs:
+
+1. In Cost analysis, select **Group by** > **Resource**.
+1. Optionally, select **Group by** > **Resource group** if you organize Arc machines by resource group.
+
+This breakdown helps you identify:
+
+- Core count changes
+- Edition differences (Standard vs Enterprise)
+- Instances that were unintentionally left running
+
+### Set up budget alerts
+
+To proactively manage costs:
+
+1. In Cost Management, select **Budgets** > **Add**.
+1. Create a monthly budget for your expected Arc SQL spend.
+1. Configure alerts at 50%, 75%, and 90% of budget.
+1. Save the budget.
+
+Budget alerts use forecasted costs, not just actual spend, to help you avoid unexpected charges. For more information, see [Create and manage budgets](/azure/cost-management-billing/costs/tutorial-acm-create-budgets).
+
 ## Monitor billing events
 
 To monitor, review [Use activity logs with SQL Server enabled by Azure Arc](activity-logs.md).