And yes, RE prices have now dropped dramatically on local vacation rental homes.Your 5-6 bedroom home strategy makes sense and we are currently seeing the highest demand for that home size.

i BRRRR locally and it's hard. 

The problem is not only that existing tenants suffer, but that local government will be pressured to pass legislation that will be extreme and engulf well run parks into spending unnecessary expense and complying with rules designed to provide residents with services they don’t want.  

I'm a local investor and agent.

One lease for the entire house.I've got loans with 12-13 banks in my market (Columbia, South Carolina) and almost all of them are smaller, local banks.

I would speak to a local realtor that can advise for what to build that would be in demand 

All of the listings are the same, fake.Go to local meetups without an ask.

I already have a B.S in Engineering (~10 years ago) from a 4-year university, so I'm thinking to enroll at a local 4 year University that offers a minor program in real estate.

Also, none of it generally, unless your local municipality reuires otherwise, requires a permit. 

I'd also suggest reaching out to a local agent in your target investment area - they'll have good referrals to provide you for your lending needs.