I'm a realtor/investor/str specialist in Hilton Head and too have properties in both Beaufort & Charleston, as well as several STR's on HHI.Both plays are great - Beaufort due to the low acquisition prices & immense appreciation potential.

I I have heard from several people living in the outskirts that Counties are adopting new septic standards based on, no kidding, the UN Sustainability Goals. 

I think you might be at a point where comfort for you and your family should play a bigger role than it did before when it was just the two of you. 

In 2023, Forbes recognizes 7 of the Fortune 500 companies which are based in Saint Louis.

In WA you can get new construction, but that is far away that I don't expect Seattle/Bellevue tech workers to live there.My boss suggested Pittsburgh (emerging tech hub), my coworker is based out of Atlanta which seems to still have affordable houses and seems to have lots of tech jobs. 

You can get plug-and-play internet, no wires no dishes, for as little as $30 per month.

Having centralized AC could be a big benefit to your tenant base which could improve rent.  

So, look at comparable rentals to see what you believe market rent is and base your decision making on that.

They can provide personalized guidance based on your specific situation and goals.

I've done a few dozen flips, a couple spec builds, bought and sold 3 short term rentals, bought and sold 2 long term rentals, and bought and sold a few commercial deals.I love what I do but the lately I've been craving adding something else to my plate that is more service based (but still related to real estate).