This is is just an example.

Say I was getting a loan for $100,000 that covers purchase and rehab. I want a partner to bring the 20% down payment to the table while I do everything else. What would you offer said partner in order to make it worth it for them to put down that $20,000, but also make it worth you doing all the work? 

I would also love to hear how you actually make deals in order to use OPM. How much is someone covering the down payment worth in the grand scheme? How does everyone win equally?