Project Manager Compensation?

[Troy DeLong]

For any of you medium to high volume flippers, I'm curious as to how you compensate your Project Managers. Our team is shooting for 24 Flips this year (and on-schedule so far) and we're struggling with our Project Manager. The original plan was to be 100% commission, based on metrics like net profit after the flip is sold, size ($) of the remodel, finishing on-time and under-budget, etc.

Meeting our average profit per flip and doing 24 / year, our PM has the potential to make around $72,000 / year. This is 1099 and the schedule is SUPER flexible. Pros and Cons of this compensation plan are...

* We could lose money on a project, or make twice our planned profit. 
* The amount of hours spent managing could vary, based on size of remodel and number of contractors involved (10 hours or 80 hours, paid the same).
* The house could sit on-market a while, meaning the PM doesn't take a commission for 6-9 months on that project. 

I'm hoping to get some feedback. What is everyone else doing for Project Management? Compensation, full vs. part time PM's, number of PM's, duties & responsibilities, etc. Thanks in advance! 

- Troy