If they have already broke ground, then you can bet they have projections on revenue. 

Here are basic stats on single-family home sales for May 2019 for the City of Austin and the greater Austin area:Major commercial real estate developers and top-tier tech companies continue to place large bets on the continued strength of the Austin and Central Texas economy.

I think 200$ plus is needed to have an actual cash flow that can be a safe bet.

If you look at the properties listed for sale now I would bet the owner probably purchased it 10-15 years ago and they are selling for around the same price they purchased it for.2. 

Wondering what’s my best bet as I had contacted a local bank which only willing to do it on the purchase price.

So, I'm starting again and taking it step by step for I think would work bet for me. 

If you can qualify for an SBA then by all means that is the best bet but there is a scenario that would work that includes you taking on a commercial loan or even a bridge loan just to get into the property until things are up and running 

A) Spending $5,000 a month on overheadb) Spending $5,000 a month on overhead, putting earnest money down on a house, betting on yourself that you can sell it in less than 30 days?  

After that, all bets are off.

I bet @Alexander Felice listens to some good ones too.