cost accounting to show revenue AND item cost from an AR invoice.

I would like to use the cost accounting to create a P&L for looking at financials from a customer group rather than the item groups. This means I currently run financials based on postings via item groups. But we also want the perspective of Sales and COGS for customer groups, no matter what items (item groups) they buy. so I will make up cost centers for each of my customer groups.

I can get revenue from Invoices. I can get expenditures from AP invoices. But I also want costs of items that are sold to these customers to be reflected in the Cost Center Report. this will be me a true margin/gross profit by customer (cost center).

I am not seeing where I can get the item costs from invoices into my cost center accounting reports? Or is it just not information available and I will have to do something custom in Crystal?

Thank you

Laura