How do you set this function: I would like guests to be able to manually control the heat/ac, but would like the range of temperatures allowed be between 68 + 78 degrees.

In my opinion, some associations have way too much control and tend to take advantage of the out of state investors (not all of course).Is your preference to purchase another STR if a 1031 is the play?

The best way to work subject to deals is if you are in control until the loan is paid off. 

Like others have mentioned, you will pay structurally more for a home warranty than self-insuring for the cost of repairs.This may be worth it if the value proposition was that you could be hands-off whenever a covered item breaks.In reality, it adds significant overhead because there is the claims process and you give up control of the repair timeline and quality as you have discovered.

Own (or Control) more stuff that puts money in your pocket today or in the future.

This is not a command and control economy, we are a free market.

Can you manage the effort and keep costs under control?  

A wiseman once said"The secret to success is to own nothing, but control everything."

I've never stayed in a hotel or short term rental where I couldn't control the temperature.

Assignment is the legal term and is not limited to the length of time the property is owned or controlled by the assignee.