The similar comps that are 1/2 mile away could be used as well, since that is within a good perimeter as long as that doesn't end up being a different neighborhood or cross a major artery. 

Great 4 bedroom 2 bath family home that we sold for a great profit.

Tenant paid me electronically using one of the major online services.

Currently own one duplex which we lived in for a while, but are now renting both units with a nice monthly profit. 

The profits would then get re-invested into the next home and continue the trend until I am able to able to build the next home with the profits that were made from previous sales.

You will, basically, be starting a flip from a negative equity position, and you'll have to dig out of that before you can turn a profit.

In my opinion, getting these right is the primary concern.There are several ways you could structure the finances and profit split between you and your partners, and you'd probably want to consult an attorney (on the structure and terms) and CPA (on the tax implications).

I can get a complete flip done for $30/sf, but that would not include roof, foundation, HVAC, major electrical, or major plumbing.

I do not believe any of the major metropolitan areas such as Dallas, Houston, San Antonio or Austin participate

One of the major considerations is the price you'e going to want to pay for rent or to buy.