I think those are the two numbers that can fluctuate once sale is complete. i'm not sure what section of Houston property is in, but insurance could be high.

From my experience, real estate is like any other stock, it will fluctuate. 

Currently 5.5%+1%=6.5%.You can see the history of the Prime Rate here to get an idea of how it moves: http://www.fedprimerate.com/wall_street_journal_prime_rate_history.htmNote that it hasn't fluctuated more than 2% in the past 10 years, and doesn't typically move up or down very fast, so it's highly unlikely you'd ever see a jump from 3.99% to 6.5% in a single month. 

Do any necesssry repairs and that’s really it.The electric bill will fluctuate up and down depending on the season.

I guess as I consider that route, one concern that comes to mind is the seasonal fluctuations as well as other big factors that can affect the travel industry, compared to long term rentals.

What key factors contribute to the financial advantage or stability between these two rental models, and how do market fluctuations impact their respective profitability over the long term?

DSCR lenders -  Because most of them sell their loans the pricing (especially 30 year) fluctuates a lot.

Though I'm sure it's fluctuated since I last looked it up, Alabama was 42nd in overall tax burden, with Tennessee also strong at 46th.

It feels weird someone is heavily invested into investment that's still not yet matured and demand fluctuation is still too high.

The only constant I would be able to foresee would be my desired profit but even with unexpected problems that could fluctuate too.