Have you ever partnered with the homeowner on new construction?

[Jonathan Steingraber]

I'd like to throw this out here to see if anyone has any input.  I have an opportunity to partner with a homeowner that has a house on a double-lot.  We have a very high chance of subdividing.  He has multiple cash offers on the table.  One is from a builder for $200k more than my offer but when I brought up the idea of partnering on the deal with him so he could make more money than just selling it outright he loved the idea.  So basically we would have a contract that allowed me to subdivide his lot, then knock down his house and build two houses and we would split the profit.  I've done a financial analysis and he will make $250k more by partnering rather than selling and it creates an opportunity for me to be able to do the deal vs losing out to a builder.  Has anyone ever done this before? What terms should I consider etc? Any ideas would be appreciated. Thanks.