So if you buy a 100K home and you put down 20K you'll have a mortgage of 80K @ 5% for this example your payment would be $429 and say the rent is $600 you can use 75% of that which is $450.If you make 2K a month here is the DTI breakdown which should be your biggest concern with what you're trying to do.  2K + $450= $2,450 of incomeDebt: 429 + ( New home payment ( $750) ) = $1,179.00  New home would be the primary residence that you talked about buying.Assuming you have no car payments or c.c. payments or personal loans your debt to income ratio would be 48.1% which is acceptable under FHA guides ( up to 54.9% ) but pretty high for conventional ( 43 and under is pretty secure but I've seen up 49% with major reserves)  You would also need 429 x 6 = $2,574.00 in reserves for your Investment Property6 months of reserves = $2,574.00Total income $2,000 base + $450 ( 75% of 600 )Liabilities = $1,179.00I know sometime I'm all over the place but plug in your real numbers with these and add taxes, insurance and credit cards, car payments and any personal loans and try to keep your total DTI under 43%For taxes do 1.25% x the sales price and .3% x the sales price for Home Owners Insurance. 

When you said a standard purchase agreement, were you referring to a CAR RPA (residential purchase agreement)?  

Contractors are below used car salesman from what I have seen.

While I learn, I am working towards selling everything I don't need... my cars, large house, etc.

@Brandon Turner The podcast have replaced music in my car.

Much in the same way your gas, car wear and tear, and time to travel to your local broker to buy IBM stock would not be reimbursed as an IRA expense.

There is no room to squeeze the can between the car in the driveway and the house so they put it near the front of the house to get the car in the drive way to be positioned so they can move the can out for Monday morning early.

Including a detached 2 car garage I get $1250 rent.

I would love to retire and buy a new car every year (cash) because I can :-)  I now have a duplex and a SFH.  

If you're truly living there, pay the utilities, have that address on your car registration and drivers license and get your mail there I wouldn't think you will have a problem.