The interior was made up of high efficiency HVAC systems, contemporary lighting, and electric water heaters.

If it can be used as a STR it's going to have septic, well water and need Starlink for internet.

That means new roof, HVAC, water heater, landscaping, painting, upkeep and so on.

8 - What type of natural drainage will there be on the site/9 - What type of water supply will you be using?

The first farmer tries to plant, water, and harvest everything himself.

When it was clear water was running from the unit.

Appears the guests may have left the faucet "on" when the pipes were frozen and when no water came out, forgot to turn it "off".What may have caused the overflow of the sink is maybe the drain lines were also frozen?

It costs the same thing to fix a hot water heater or remodel a bathroom on a $200K house as a $100K house.   

If they can't do that, keep shopping.This may require digging up the foundation, sealing it from the outside, and installing a french drain to keep water away from the walls.

Start with maintenance notes that you may regularly reference, such as air filter size, water shut-off location, etc.