A strong “Core 4” can make managing your investment remotely much smoother and prevent a lot of headaches.Also, as you narrow down cities, pay close attention to factors like job growth, population trends, landlord-tenant laws, and short-term rental regulations.Happy to connect with you, and good luck as you jump in!

Including one that prevents a unit from being rented for less than 6 days. 

Might prevent him from buying another home for several years.

Many people have limiting beliefs, a mental barrier that prevents someone from achieving their goals or living fully, so they sabotage any hopes of progress through words or actions.

What prevents them from doing that?

It might be worth talking to a lawyer but not sure if it's small claims or worth it.Also, you might already have all of these things but for future prevention:- smart thermostat (so you receive alerts when the inside temperature dips below whatever preset you have)- Minut (or similar device) would also alert you to the inside (and outside) temperatures; for example, I have 2 devices inside the house and outside on the hot tub deck.

It can be a normal problem but you can prevent it with some certain measures.

What specifically did you expect them to do to prevent them?

If multiple people chose another house for the same reason or avoided yours for the same reason, maybe you can pivot a little to prevent that issue being a factor for future prospective renters. 

Explain your situation and see if there are payment plans or hardship programs available.The BiggerPockets forums have threads on tax liens and foreclosure prevention: https://www.biggerpockets.com/forums/41/topics/766025-surplus-funds-unpaid-taxes-in-foreclosure-saleAn experienced real estate attorney can advise you on your legal rights and explore potential solutions.Have you spoken with your local tax authority yet?