After that, any roommate amelioration of your expenses would be a bonus!

Any extra cash flow would be a welcome bonus. 

But at 75/25, it changes to 65/35, accounting for my extra money, but also his bonus percentage.

These jobs are often business graduate students that gets      ~ $15 bucks a hour in Silicon Valley and a bonus for successful deal making.

I'll be sure to mention your name to get that referral bonus for you. 

The way I see it is the rentals I am looking to purchase will generate cash-flow and any appreciation is a bonus.

I currently have a full time job where I receive pretty decent bonuses and RSU's so long term I'd like to use that income for RE investing but it will probably be at least a year or two before I can do that because I'll probably use that income this year to buy a house for my family.So short term my idea was to move the money in my Betterment account to a self directed IRA.

If everything goes to plan I then use this 10% to give me and the contractor a small bonus at the sale of the house. 

The front house was a 3 bed / 2 bath with a bonus room (1100sqft) and the back house was a 2 bed 2 bath (800sqft).

As a bonus, this is a much better time of year to be finding tenants  vs.