Short Banks are the ones making the rules. Typically, sellers (the borrower) approve the offer, and then forward the offer to their bank. The banks dictate the terms they'll take...your buyers either agree, or don't. Most of the banks I've tried to work out "bank paid closing costs"...I get a "no go" regardless. Not sure why, and have never gotten a straight answer to "Why."
I'm not sure even if it matters it FHA...or anything else.