Low or no down, seller financing and low or no interest with a balloon payment later is the holy grail (location, building condition, market also matter but it sounds like you have all that).

FICO is 780+ and currently have 4 other investment properties including 2 STRs in the same market we are trying to close on in West Virginia.

Fort Worth is a great market to get started REI.

The cost for the unit was about 40% below market value.

If you end up moving in that direction and putting all the dominos in place, the last thing you want is to get towards the end and have the deal denied because of that.Unfortunately, most GAP funders keep regional to markets and people that they know and they keep them close to the chest.

Rents were below market at $750 and $820, while similar units rented for $1,000.

If the latter, how does that look on a day to day in terms of operating, marketing, and the ownership structure?

I wish you the best of luck but your idea if scaling is severely flawed. 

Guest breaking down their markets and strategies gave me a lot of insight.

I am wishing everyone great success!