So my question is, when partnering with an investor/friend/family member how do you legally set up the purchase to ensure cash flows are paid out as agreed?

I don't need a traditional duplex, as I agree MOST are in not so good areas.

My son has a cross country tournament at that time but if the calendar was open I would try to attend (I find them to have been worth the time) .

I totally agree with that for newbies that “no money down” is fairly impossible.

@Glenn PaulsonI agree with @Will Barnard instead of cashing out your IRA and being subject to an early distribution fee, and higher income taxes, you could transfer those funds into a self-directed IRA and purchase the property in the name of your IRA.

While I agree with @Will Pritchett on the over valued part I feel we are far less over valued as some areas of the country but you are buying for cash flow not some much as equity.

Second, those that are sharing a home with you must agree to your house rules.

I agree with your last statement "...higher than inflation of 3-4%  then I'm good".  

Is that why you're asking about a commercial real estate/investor in wine country?

I agree with @Nick Watkins on this. if you are worried about " fair price" hire an appraiser, few hundred dollars, and let them tell you and your sister the fair market price. then deal with this through the family. if you list the property then you are dealing with realtors, closing fees and taxes.