After a year of not seeing any cash flow and rent excuses, I terminated them and wanted to shed light on the experience. 

Take a look at Reno, it's is a solid area for rentals because of the limited new construction, tech and manufacturing jobs moving to the area (Tesla, Apple, Switch etc.) along with the lithium loop of mining and recycling to manufacturing batteries and vehicles.  

The subto seller's owners coverage (other than any liability arising from the breach of a warranty) would terminate at the subto sale.With a land contract / land installment contract / contract for deed (executory), coverage would continue (IMO) until the deed into the buyer was executed because the insured retains an estate or interest in the Land (legal title) until that time. 

My cousin has terminal cancer and is in hospice and will pass away in 6 to 12 months from now. 

Oakland's worst areas long term, in terms of appreciation will IMO produce far more wealth than properties in Indiana and many other parts of the country.

If none of those solutions will work, and they are MTM, you can give them notice and terminate their tenancy, repair the stairs and re-rent out the unit. 

I like that they have built-in solar panels and batteries to power the home in the event of a Grid-down sitaution.My concern would be: will they be valued as manufactured homes are?

Mid-term is a made-up term that doesn't change the rules you have to follow.I believe you are in Virginia where monthly rentals require you to give notice 30 days of termination.

No unregistered vehicles and no vehicle repair on property is in the lease (although I wouldn't have a problem with emergency battery and tire situations, I prefer they don't change the oil on the property. 

This is essentially giving you some of the cash from your improvement (presuming they are significant) , as well as a steady stream of income into the future - which helps you long term in numerous ways.