How can I reflect buyer broker commission in MRIS when it's a short sale?

MRIS compliance will not allow you to indicate that a third party will determine compensation for cooperating brokers based on negotiated contract terms, therefore; you must put in a coop commission amount you will honor - no matter the net commission agreed to by the bank. This is exceedingly challenging, of course, because you do not know what the bank will approve, so you may be left with very little commission as a listing broker if the bank hits the commission hard. My suggestion is to offer 2 to 2.5% because in most cases the commission doesn't move lower than 5% during bank negotiations