When creating a Payment for a Business Partner which
already has a bank account with the credit card
details, then the information should automatically be
copied to the payment. The same goes for Orders and
Invoices where it is also possible to enter credit card
In a simple implementation the callout would just check
if there exists a credit card and then copy the
information from the first account found. In a more
advanced setup the system would prompt if there are
more options and also handle bank accounts etc.
Another simple solution would be to add a
C_BP_BankAccount_ID to C_Payment and just let the user
select from a drop-down list and then use this information.