It likely means you have that amount of coverage when caused by another peril and as mentioned it's typically a significantly lower limit than other coverage amounts.If a pipe bursts, it will likely be covered. 

I will mention that a hot tub could really increase the frequency of bookings. 

Of the things you mentioned, seller finance is one to focus on if capital is low.

The GRID meetup in Edwardsville (also mentioned above by Rich Groves) is new but I understand it's drawing lots of folks. 

Purchasing a STR in a somewhat sketch area is a terrible idea and as others have mentioned, is going to open you up to potential issues. 

When you mentioned you did your homework on the turnkey property, if that were the case you would have had a really good idea what the property was worth before you offered on it (of course sparing the occasional rogue appraiser, which may be what happened to you... idk) and certainly before the appraisal.

It's worth mentioning the STR regulations are relatively new, and I think some properties currently operating are basically grand-fathered with the old permit, and I don't know if being a new owner one'd be able to get a new permit if it's not in the designated location.

You are very detailed about your complaints, but never mention basic important details such as what kind of rental agreement was given to these tenants?

You will be waiting a long time - that as mentioned was a black swan event just like when they went to like 18%.Historically speaking expect rates to be between 5-8%. my recommendation to anyone buying real estate today is if you buy, expect to hold it for atleast 5 years 

A good friend of mine recently managed to pick up a modest duplex outside Phoenix that looked risky at first glance.. low rents, older neighborhood.. but with a few smart upgrades, it became a steady earner in under a year.You mentioned your worries about remote investing and the challenges of managing properties from afar.