When partnering with a contractor - what is a fair $ split?

[Rick Mapes]

Greetings!

I have a contractor that I've worked with quite a bit over the past few years, his work is solid, pricing if fair, and is just a real decent fellow.  

I'd like to get into buying more distressed properties, and bring him into the fold as a partner on the property, so he is motivated to do the work as quickly, and as close to budget as possible.

On to my question - if you were financing a project (and materials) and working with a contractor, what % of net profits would you be willing to split with said contractor?  Has anyone set up a deal like this before?  If so, what was your experience?

Thanks in advance!