Judging from the fact you have someone there 4 months and still haven't filed for eviction you should probably hire an eviction attorney and a property manager.

Likely just light cosmetic, fix ups, bath and kitchen remodel, landscaping. 

With your extensive experience in remodeling and radon mitigation, you'll be a great resource for anyone needing radon testing or mitigation solutions.

I have no affiliation (or ever heard of them until today) but they are HQ'd in YT and appear to be investment real estate friendly based on their filings.

They usually have a process for filing a claim with the city for damage caused by them, and they may be willing to cover it.

It also makes negotiating things like insurance rates easier because you’re seen as a business, not just an individual.Of course, there are pros and also cons, like setup costs, filing fees, and more paperwork to keep up with.

I have spoken to many active investors that filed bankruptcy in the financial crisis.  

They sent me the Excel files over and I was made to believe it was optional.

One building was a 1920 house remodeled in 2012 and the second building was newly built by a contractor in 2012/2013.

Also there could be a good chance the borrower files BK if they are still alive.