Repayment of principal is merely a balance sheet movement that never hits the P&L.Your accountant should look to what was done with the proceeds over time to determine accounting treatment as well as interest tax treatment. 

The two solutions towards the top of my list (selected as an industry neophyte) are Buildium and AppFolio. 

The solution to me seems to be periodic cleaning of the closets, but the tenant wants me to “fix” it.

These loans and the process, level of scrutiny and costs associated with them, are geared for longer term solutions to hold real estate.

I'll be curious to hear your chosen solutions. 

Until family gets involved we would accept checks from this person and then work with family to find the best solution for all.

The question is, assuming I go for the heat treatment, will the entire house need to be treated? 

The next several months were extremely stressful; the tenants left, I watched my bank account get lower by the day, and I spent every waking hour trying to figure out a solution. ...for weeks, I thought I was headed for bankruptcy, and I assumed the entire house would need to be razed (who would buy a house that has regular, unpreventable floods?).

@Tim Herndon I appreciate your solution oriented answer.

I had NEVER had a panic attack until I went through treatment for cancer.