As Todd says, things might start heating up if oil prices stay in the tank.  

The owner wasn't interested in fixing it up, I bought it with no contingency on the septic tank and got a decent deal. 

Make it known that there is zero tolerance for non-building residents to use the facilities.If the Unit provides "additional storage" like say a 3 car garage, or some sort of barn/shed outside of the building, monetize it.

Our oil tank is  1000.00 to fill but it lasts more then a month.

As an improvement on this technology, we have a test installation using electric resistance thermal storage units ... essentially larger baseboards filled with bricks as a thermal mass.  

Time to bring your Sherman Tank to this gun fight.

I still have some of my things in storage at the house, but haven't really missed it, and probably will not be going back to get it. 

A hot water tank, furnace, satellite receiver, air conditioning unit, security alarm system or water softener, for example, could be rented by the homeowner.

They might have burnt out if the tanks wasn't installed correctly too.   

With as cheap as storage is these days, either locally on an external hard drive or even better in the cloud, there's not a big reason you can't keep the records for years.