We charge customers upfront for 100% of the sales order value and then typically ship the order in 2-3 transactions. We want to be able to record the entire prepaid credit card cash receipt up front in our GL, and then as we do partial line item releases from the sales orders, have the invoices created and have the prepaid cash sitting on the customers account get "automatically" applied to the each invoice transaction until everything has shipped and all the prepaid cash has been applied and the customers account balance is zero.
We don't believe SAGE 500 handles this "out of the box". Is there a recommended best practice custominzation here or perhaps even a third party add on available?