On the Dashboard page in your admin, you can get a report of your financial stats for Buy Orders. This is a tool useful for seeing how much money you have paid out for buy orders within a given timeframe.
Go to the Dashboard page in your admin.
Under "General Status" click on the button for "Buy Orders"
3. Under "Buy Order Stats", below the table, set a date range, then click "Update"
This will update the chart to show you how many buy orders were completed within that date range, the total amount paid out for them, and a breakdown of how much was paid out for each payment method.