I have had a tarp put in place to stop the moisture from getting in.  

I would suggest a newer build [1998-up] like a subdivision "vinyl village" home to purchase.These will cost a little more than an older home with the same rent but are much newer, typically on a slab [no moisture issues to deal with] and are easy to rent and/or sell in the future.One downside of this type of home is that most good markets [Indianapolis included] have been invaded by the Wall Street Hedge Funds and they have or are buying up this product at record rates.

We would have noticed how bad the moisture damage was right from the get-go.

This is a problem created by them so they are responsible for repairing it.Mold requires moisture and a food source (dust).

I would be gentle with how you relay that you know they are delinquent.

They have a range of just scratch & dent, to gently used, and down to pretty well used appliances. 

Hi @Ben Morand, How about working in Orlando while you're in college, but at the same time start gently marketing to your sphere of influence in Gainesville, providing them with information on a once a month business that helps them get more value, safety or enjoyment out of their homes, or updates them on the market?

Mold is an indication of moisture and if you don't figure out where that's coming from and correct it then the mold will be an ongoing problem.  

I'd just be concerned because it says moisture resistant but not waterproof -- hard to argue against your soaking experiment though. 

Everything else the tenant has done has been of her own accord, despite me gently and repeatedly stating that "Denise has it covered."