I have some rentals that still have 1970s wood paneling, and I love it because when someone moves out I can simply wipe it down with Murphy’s Oil soap and I’m done.

It has glass fuses and oil heat to give you an idea of what I’m working with.

I can tell you that the house next door which is 1930's vintage and is a big old farm house with 4 bedrooms and a couple bathrooms and had a oil boiler with radiators was just retrofitted with a gas furnace and vents run throughout the home so they can also add central air and they were quoted $24,000 by a local HVAC company. 

Which would add 400/mo - 4,000Current owner says he pays roughly 3,600/year for oil and electric (there is a 4th panel for the “house”)2017 town appraisal lists 260kAny of you quick thinkers out there have advice?

Completely renovated with refinished original hardwood floors, fresh interior and exterior paint, granite counter tops, and oil bronzed fixtures.

Garage:  oil spills? 

It’s got glass fuses, and oil heating to give you an idea.

@Patrick Philip   The whole tone of this thread is that you don't trust contractors, you're smarter than they think, you know how much everything costs and you want to shave every nickel . 

@Sean AutryI've also seen a 120 lb German Shepherd mix do irreparable damage to 3/4 in. oak hardwood, too, but for my money, if you allow pets in your rentals, as we do, nothing beats semigloss oil-polyurethaned solid oak and ceramic tile for longevity, absolutely nothing by a long shot.I realize this is zero consolation for you at the moment, but I thought I'd contribute it here for others thinking about have pets in rentals.

At this point, the game plan is to use a TSP-based solution to wash the ceilings & walls as thoroughly as possible to remove the nicotine/tar buildup, two coats of oil-based Killz primer on the ceilings & walls and then paint.