How likely is the local government to honor a 70 year old variance?

As I'm sure you know energy has never been an open market, every form of energy receives significant government support, and solar is no different in that regard. 

I understand this is some type of federal government assistance program for low income areas.

Bonus points for more recession proof industries (health care, government jobs, education)Median income over $40k (your tenants need to be able to pay the rent)Average home price over $100kLow unemployment rateLow housing vacancy rateMarket with a strong affordability factorLandlord friendly  Those are just some examples. 

Without substantial government subsidies, tax breaks, etc. the numbers just don't work.There's a saying among RE investors who deal with large apartment complexes: "If you want a C-class property, build an A and wait 30 years."

If a tenant is receiving government assistance (Section 8, Abode, Vash, etc.) then they are NOT restricted to rent control. 

Luckily we sold the property to a buyer who was desperate to get into this particular complex and was receiving grant money from our state government to cover her down payment.

All of which depend on the sub code officials governing each trade in the town.

Unrecorded debts could be Mechanics Liens, Welfare Liens, Government Liens or Nursing/Medicare Liens.

They pretty much deny everyone not on the beach, and their reason is because all the hotels are on the beach, and they say that they'll allow the condos on the beach to govern themselves.