Some states require 2-3 years’ experience as a loan officer first along with you need to open or rent an office space (brick and mortar).

Although you don't need licensing for many loans, it's probably a good idea to deal with and verify the licensing of NMLS licensed lenders.

We are building 2 and are interested in more. 

If you don't already have a CPA, I'm more than happy to provide recommendations.

I recommend checking with your lender about their specific requirements.

Which neighborhood is this in? 

Since I have been semi successful with this approach I can see it working. 

With the sale of the rental my income was over 150k.

I am happy to provide insight as I work extensively with foreign national investors in the US.

If it was me...I'd check with zoning to find out how many dwelling units I could build, and I'd find what the requirements are for those units (type of house, height and setback restrictions, etc.).Then I'd find out what local builders think the cost to construct would be - just get a cost estimate per square foot for 2 or 3 different levels of finish.