Is haveing a COC return of around those numbers pretty typical in Katy in the market we are in? 

3 x 2 BR Apartments @ $700-$750/mo.1 x 1 BR Apartments @ $550/mo.4 x Studio Apartments @ $400-450/mo.Commercial is 1450 sq. ft. and should rent at $11-12/ft.All units have completely separate utilities, except water.  

That typically is investors.

How much would that typically run?

@Ray P.Be careful with phrases like "promissory note to myself" relative to using a SD IRA...typically you cannot directly benefit personally when using a SDIRA, all transactions have to be done in the IRAs name.With 15 K, I would probably:- Leave it, invest it as best you could with stocks.

From this data, you can utilize a website bestplaces.net that will give you a breakdown of the percentage of homes that sold, in various price ranges, for a given zip code.

At about the same time, I go to serve legal notice just in case they don't, to pay utilities or vacate, when I find out they have not paid utilities.

You could utilize the cash as the down payment and you would be able to purchase a nicer property.

You want the net income after all expenses like, maintenance, utilities, taxes, insurance, property management (if needed), if the property is vacant figure that in, and Cap Expenditures (any big ticket items that might need fixing or replacing once you own), things like the A/C unit, water heater etc.

Brian Jameson If you show a loss YoY on your returns, most of the traditional long term financing options will be closed to you, including Fannie/Freddie and typical bank loans.