Summary - This is what I have learned from reading through the posts and I am going to try it out soon for the first time. Any other tips?

The CSR needs to specify the split amount after you swipe and input pin, not before. Keep payments under $2000, or 1998.12 with the 1.88 fee works. So they setup everything for billpay, you swipe your card and input pin and then they specify amount and then debit key. If they are unfamiliar with how the billpay works, they insist on pressing the amount and debit key, before the card swipe and the system errors when they try to do it.

YMMV. They don't need the paper bill just the card number or physical card, but some clerks insist on the bill.

Metabank cards work good.

4 swipes per transaction under $2000. Fee can be paid in cash. Some WM don't let you split payments, so $500 at a time is it.

5 payments to one cc per 30 revolving days.

This system is not at all WM anymore, so only MoneyGram is available at a higher fee.