Remember your situation is unique so it's important to consult with a tax advisor or CPA to explore all available options and ensure compliance with tax regulations.

Wholesalers are not regulated by Real Estate Agency, therefore not required to abide by certain laws and disclosures.

If you're going to do it alone, make sure you your due diligence: estoppels, inspection, review, consult with a local attorney familiar with the local regulations, etc. and good luck.

I do NOT trust “regulators”.

Think about it, was it harder or easier to plumb a house with cast iron or galvanized piping or Pex.

However, there is no specific holding period contained in the tax code or regulations and there is no "safe harbor." 

As long as you listen to your insurance company's regulations as well as your local ordinances you should be fine. 

And the locals in Highlands have been fiercely debating STR's and regulations for the last few years, so I wouldn't be comfortable buying there.

However I did note that houses are mostly really old, e.g. 100 years or older... any idea if this poses challenges in things like lead paint presence, outdated wiring, rusty plumbing, etc., or have many of the homes already been updated?   

We decided to outsource major tasks such as septic installation, plumbing, heating, and carpentry, while handling smaller projects ourselves—a decision that proved beneficial.