importing invoice, receipt and inventory updates

Hi all,

We're building a POS system to handle sales, invoices and receipts from customer.  In some cases the invoice is not paid straight away, so this can be handled by importing the invoice from POS and upload it into AR interface table, then use autoinvoce to generate the invoice into AR.

In other cases the invoice is paid straight away by customer.  I am not sure how to handle this as autoinvoice does not handle receipts.  Is there any public API for receipts?  Does that mean the invoice and receipts data are sent seperately?

Appreciate your help.

laura