The states that I know require you to try to mitigate your damages if a tenant breaks a lease early.

It sounds like regular maintenance issues, some of which were tenant-caused. 

I regularly attend COIN, and also Tommy Harr's events.

@Joel OhA regular insurance policy can refuse your catastrophic loss claim if they find out you were renting your house as an STR.

You do not work with someone who repeatedly breaks the terms of the lease.

If not cleaned well, dried, and oiled regularly, cast iron can rust.

Putting less down may subsequently put you in a break-even scenario or possibly even a negative cash flow.

If we the landlord would want to break the contract before the end of the multi-year term, we have to pay him a pro-rated fee to reimburse his investment

This gives them a chance to tell you if anything is wrong with the unit and if they do not reply or say that everything is going well, it will help you if they break stuff and/or try to get a refund later. - Honestly, I haven't had that much issue with people breaking things, I have had more people trying to fraudulently get a refund though. - Set aside a % of each host payout you get for future repairs replacing furnishings, expect it to happen, and then you will be prepared when it does. 

He breaks down using Self-Directed IRAs (SDIRAs) to invest in real estate—like rentals or flips—and keep the profits tax-free.