If this is a partner that you want to grow with then I'm lean more toward being more generous and treat this partner as an equal equity holder so that this person is rewarded well and will likely be there again to fund future deals.  

So far I have used Rent to Rewards for two purchases and have been happy.

Ed,For investing in MF, some popular read all available on Amazon:Steve Berges - Complete Guide to Buying and Selling Apartments.Dave Lindahl - MF MillionsPaul Moore - The Perfect Investment - My friend Paul, former Ford engineer, entrepreneur and now MF syndicator has done some interesting research on why MF is a great investment (focusing on trends, risk vs reward, etc).  

 I have newbee investors on TX who are considering a double closing.  What are the risks and negatives  with this type of closing?

works at our Church and obviously doesn't get paid much, but the work is rewarding and satisfying!  

Ridiculous that guys like this are actually rewarded for bad behavior.

For such a little xtra reward?

Aside from all the hidden costs mentioned by other, I think you need to consider risk/reward. $75K in rehab is serious work and 10% seems low on contingency unless you are very seasoned and there is no hidden work.Making 10% on a complicated deal seems risky.

As a side note, use caution finding someone of Craigslist- I have learned the risk far exceeds the rewards when sourcing something like this out.

Just as in any other business venture you have to way the risks vs the rewards.