Here's a primer:The two basic kinds of paint of oil-based and water-based.

He claims that they forgot to includes charges for a tank if fuel oil at the closing.

I have had to answer the infamous late night roof leaking phone calls, and dealt with: leaking toilets, leaking water mains, faulty electrical panels, broken water heaters, broken furnaces, underground oil tanks, troublesome septic systems, late rents, tenants dog eating the walls, unresponsive tenants and every other real or imagined rental horror story that people who are either too afraid or unwilling to, use as an excuse not to invest.

Like a couple years ago when we were building  an addition and found contaminated soil and an abandoned oil tank .  

Specifically, the backside of the oil refinery, which is probably why I got it so cheap. 

Simply painting garage walls in a semi-gloss white & cleaning oils stains off the floor say "this house was nicely maintained" and are among the cheapest things you can do after removing trash & mowing the lawn.One under your belt at least gives you a more "legit" standing with lenders, contractors, etc, on the next one.

I heard that Alberta is more cyclical and oil-dependent?

Now there is more oil there than the middle east.

I was nervous initially thinking that I was sold snake oil.   

The problem is when people say this process is snake oil, magic or double secret prime ....