Heaving and cracking of most foundations can be due to 1) movement of the land and house, or 2) water that freezes into the spaces around the foundation. 

I find it is easier to charge the adequate rent and just pay the heat as the landlord and know the place is never going to freeze when someone goes on vacation. 

During the freeze a water pipe burst...the tenant does not have renter insurance and now decides to sue me.

If it was in winter then there would be a legitimate concern over pipes freezing.

I don't have anything to offer with your question beyond what everyone else has said but I just want to let you know some general rules with foundations:1. crawlspace - cheapest to repair, good for plumbing because they can run underneath the house and easy to repair, bad for really cold days, pipes could freeze, some people complain about moisture in crawlspace and tile cracking but that's a long term issue and you may not have to deal with that and if you do, just lay LVP2. slab - second cheapest to repair generally, worst for plumbing because to fix, you have to often remove flooring and drill into the concrete to fix leaks and I've had a house that I played whack a mole with an active leak3. basement - most expensive to repair, okay for plumbing, but your basement could leakIMO crawlspace is the gold standard for foundation for rental investments in older properties (older than 1950s).

What if we have a deep freeze and your pipes freeze and burst in your vacant property, or it gets vandalized and taken over by squatters?

Normally dealing with a problem like this is a big challenge, but dealing with it over Christmas eve & Christmas day with extreme freezing temps when no one wants to work adds significantly to the complexity. 

You should know beforehand where your plumbing lines run, to the street and which exterior walls have runs as these are usually the first areas to freeze.

Around 5pm tonight, temps will drop back down to freezing and by midnight we'll be at a crisp 7 degrees.

Tenant shall also be responsible for any plumbing system freeze-ups occasioned by Tenant’s negligence."