As this question is both SD & FI relevant, so posting in FI.
Have you come across a scenraio where customer makes ONE BIG payment (or say downpayment). And we create multiple Sales Order which then considers this in billing invoicing correctly. Also how can we post this ONE Time payment in system with reference to a dummy Sales Order or a Value contract. If there is a Std SAP Solution for this please let me know.
I read many articles on pre-payment / down payment. But down payment are made for or with reference to Sales Order. I also checked Std downpayment and tried with AZWA, AWZB & AZWR. But Sales Order is must for tracking and posting.
I read that pre-paid account can be implemented in CRM as we dont have CRM any advice on how to implement in SAP will be helpful.