Profit Sharing between private land owner and Contractor.

[Matt Johnson]

I know a few local builders and have a land lot that I would like to pursue an agreement with one of them to build a spec house on.  My current idea is to provide the building lot only and the contractor to take care of the rest (for the most part).  Im wondering what kind of a percentage/share would be reasonable for me to ask to get out of the deal?  If anyone has any experience here, I really appreciate any advice.  Thanks.