Paint the floor with an oil-based primer, then put new flooring in after you've confirmed the odor is gone.I've seen some pretty bad houses where cats were spraying against the wall.

Don't believe anything you hear and never ever buy a crap course or product at a real estate meeting because the largest real estate clubs are the biggest scumbags when it comes to the presidents of the clubs bringing in snake oil salesmen who scam you out of thousands of dollars.Always believe that whatever crap and 'SECRETS' sold at a real estate club meeting can be found on the internet, absolutely free.

Doing 3 furnaces allowed for no more oil and the tenants now pay each of there own bills.

I am responsible for water, heat (gas or oil), common area electricity. 

@Jay Hinrichs   You have to know what kind of wells they are, what the production looks like, how old they are, oil or gas, or both, where they are, and on and on and then make the wildest guess where you think prices will be in the future and where the government wants to go with production in the future.

Given what I know it needs without even seeing it, though (new roof, fascia repairs, animal control, new boilers, lead and asbestos remediation, oil tank removal--and that's without knowing anything about it structurally or cosmetically on the inside), I'm guessing I would have to put in roughly $100k in rehab.

I usually use Kilz oil primer for this.

Early in my career, I rented to two guys making $90,000 each in the oil field.

I worked on Oil Tankers and we had 120 year Hurricane tracking charts.

You could  diversify your other assets as a “hedge” like short the home builders or buy oil.