You may have an out for cause that you can exercise.

This is a great exercise for newbies IMO.As much as deferred interest, neg-am and I/O options are very tempting and regardless of what our opinions are, I trust that you will come up with a win-win situation for both parties.

You guys agree to a pre determined purchase price and you get something like a six month option to exercise it at that price or conditional upon his moving out.

For example, if in the 30th month I decide to exercise my option to purchase the property, the purchase price would be $180,000 less 50% of the previous 29 monthly payments at $1500 (29 payments x $1500 x .50 = $21,750). $180,000 - $21,750 = the new purchase price of $158,250.

You've got a good strategy there...timing is one of the most difficult things to master in these situations.The option allows you to do the following...contract your end buyer subject to you exercising your option...not subject to the short sale being completed.

That allows you to get out of the deal by exercising your financing contingency.If you're just trying to assign your deal with out doing any fix-up, than the idea is to sell it before you have to close and come up with funds.

maybe its some sort of ancient philosophical exercise

Lets do some exercises. 

They drive to the gym....then get on the stair machine and/or do walking or running exercises.

So for example, if you block out an hour of your day to exercise, then just exercise.