How can you link customer and vendor master records in SAP FICO : SAP EXPERT SOLUTIONS

A: On the customer master there is a field “vendor” and likewise on the vendor master there is a field “customer”. By entering these master data numbers, a link can be created between the AP/AR subledger for use in the payment program, dunning routine and the clearing of open items. For example in the payment program, if a specific business partner is your vendor but
also your customer, linking their master records together will allow the open AR invoices to be
offset against the outstanding AP invoices.