Bank rejected offers,must step aside and sell to end buyer, how can I collect a fee for work done?

[Gail Smith]

I've been working with a homeowner since July. It's a rental property in poor condition in a great neighborhood. He evicted his tenant for non payment and I marketed the house @ $99K. (Assessed @ 145K) No takers, needs lots of work. He owes $90 on the property. He tried to do a loan mod but doesn't earn enough. So we decided to do a short sale. I've put in 2 offers, (1st at $48K, 2nd @ $61K) both were rejected as too low and I was told that they would now "close my file". They want $75K for it. With the amount of work needed, I think an end buyer might go to $75-$80K so that puts me out of the picture with a double close scenario. I don't want to see this guy foreclose and I would like to get the property sold. Has anyone worked something out with an end buyer to get compensated for all of their work and delivering the deal but not actually participated in the closing? This would be an A-C transaction. I've read about many possibilities for adding fees on the HUD but my lawyer's not too keen on that. Any suggestions from those with more experience?