Send her a certified letter (keep a copy for yourself) with your concerns of her not turning on the heat and the problems that can occur with frozen pipes and repair cost in which she will be liable for if she doesn't comply.Is she using space heaters instead?

If the change has occurred and buyers are now doing this, surprised not discussed more  You as the buyer is paying for the agents commission one way or another , either by a higher sales price , or by cutting a check to your agent . 

I basically just told them when they moved in that any drama that may arise from them sharing the house is between them and has nothing to do with me (as long as the house/people aren't being physically harmed).If you do end up renting to veterans I think your best bet to ensure everyone gets along is to just make one lease for all 4 bedrooms.

At the time, it never occurred to me that if you want to swindle people it is difficult and expensive to take legal action against a company that is incorporated in a different state than where they do business.

If you're sure the land will appreciate on it's own, I don't see any harm in going for it, unless of course your money can perform better elsewhere, which it probably can.

You better reach out to them days before the auction and give them a simple choice: allow foreclosure sale  to occur or allow you to take it over from them, with equity justifying your purchase.    

I was so caught up in the project in its entirety that it never occurred to me that they are 2 separate things.

Then say you want to talk to that person, and find out if in fact they are OK with theft occuring but saying you have to have a contract saying they cannot steal from you before they will prosecute it. 

California does not have a law requiring deposits to be held separately (neither did Alabama when i had Alabama properties) and it seems like a significant hassle to address a virtually never occurring event (not having money to return deposit to the tenant). 

And it occurred to me that by purchasing this property I'll be increasing my monthly cashflow 25% going from 400/mo to 500/moOf course I'm not considering this in a vacuum, I have other factors to consider like appreciation, principle pay down, etc.