How do you run a profit and loss by customer with detail of each COGS transaction?

You can pull up either the Transaction Report or the Account Quick Report, Lisa.

While a complete Profit and Loss by Customer report with all COGS transaction details in one export isn't available, you can generate two reports to obtain the information you need. Use either the Transaction Report or the Account QuickReport.

For the Transaction Report, click the COGS Total and customize it accordingly. Check out the image below for visual reference.

Alternatively, for the Account QuickReport, go to the Chart of accounts, search for Cost of Goods Sold, and click on the Run report link. Refer to the screenshot for a visual illustration. 

Once complete, manually merge the COGS transaction details with the exported Profit and Loss report.

On top of that, you can save your customized report for easy access to your tailored data analysis whenever needed.

Get back to this thread if you have any questions about your reports.