., but we have gold wheels for cars, BIG wheels for trucks, higher tolerance wheels for off-roading, and so on...

Their combined monthly income is 3X my rental amount but the man's income is in cash (he is a car mechanic).

We include my commission and negotiate as normal.

Normally, unless there are specific building code restrictions, the amount of units allowed on a lot is determined by the Floor Area Ratio. 

The question here though, why are banks turning you down for a very normal loan product?

They'll want all the normal stuff; bank account info, LES for several months, hard credit check, etc.

I have confirmed what @Garrett Brown shared -- my best option is an SBA disaster loan with a lower than normal interest rate to pay off our mortgage and then I can also hope for / pursue with others a land buyback program for those of us who have floodplain property that FEMA won't reinsure.

It's going to be a good long while before things get back to normal around here.  

The repair shop includes 10 service bays to be able to service a variety of cars.

You are off to a great start because you know you don't want to LEAVE your job to do real estate, you want real estate to be a sufficient side car to the job you are already crushing out of the gate.