Reverse engineer that and you can figure out how many properties you will need to reach that goal.Best of luck

I have ripped out engineered wood before and it was a pain.

From a civil engineering perspective, I have experience creating civil engineering site plans and permitting for apartment complexes in Houston. 

Within 1 year we were publishing in booking and a few smaller channels and tied in to a pricing engine, lock automation, setup a set of great communication workflows, etc.

But, I'm a mechanical engineer by trade and am not afraid of digging into the details to figure out if it's viable. ;)

I think I will first talk to the County Commissioner in my district, and then we meet with the County engineer.

For building in the 100 year or 500 year flood plain you will need a topographic survey of the lot and an experienced architect/engineer to design and help permit what you are wanting to build. 

Sorry to be so negative, but I wouldn't have a dude who has never turned a wrench rebuild an engine.

Would get with a local engineer to do the layout and an estimate on costs.Your buildable sqft seems really low. 

However, given the robust rental market conditions, we decided to pivot towards long-term rentals (LTR).