Give the tenants the option of moving out before it goes to eviction. 

I've looked into wholesaling, which is an option, but I have basically no connections with buyers and I'd be nervous to start with no connections.

For this situation you would have handled differently your option but the reality is you can be held accountable as a guest even if you are ignorant, nothing to do with law.  

Another option is to go to investor groups in your area (investor conferences, seminars, etc.). 

Upon retirement, I have the option to allocate a significant portion of my income to pay off all four properties.My inquiry arises from an opportunity that recently presented itself: the chance to invest in new duplexes in Indiana.

Posting on a local RE group in that area might be a good option as well to get recommendations from others

Hey Lucas, another option instead of creative financing is a DSCR loan for an investment property.

I've been in REI a long time and have seen the good, the bad, and the ugly, but $60k of damage from one tenant indicates gross negligence on the part of the property manager.I'd suggest three things: 1) Study the contract you have with the PM company, and talk with your attorney ASAP to see whether a lawsuit is feasible/advisable, 2) Get at least three bids from other contractors on the repairs (and before you hire any contractors, study up thoroughly on how to properly vet and manage contractors--there's plenty of info about this on BP) 3) Don't do any more business with the PM company (or any contractors they refer), and keep them at arm's length while you discuss your legal options with your attorney.

The house is fully updated, and we keep it in excellent repair. 

We recevied a proposal from a billboard company to build a full sized billboard. the research has been conducted and a written lease has been written and presented to us for 1k/mo, 20 years + 20 yr option, with 10% rate increases every 5 yrs.