@  3rd issue and the current pressing issue.  

Big concern if I were in your shoes is that my family gets offended pretty easy so I wouldn't press too hard if they feel like I'm trying to cheat them out of their inheritance.

In order to match homes with renters, I often do quite a bit of cold calling to talk about executive leasing.

I'd look into the possibility of installing heat pumps with electric heating elements for very cold days(one per unit, hopefully, in the units which currently have electric heat) these can be installed in the window much like typical air conditioners and they will function as air conditioners in the summer- some can be installed through the wall.

Since you are located in a cold climate, I would keep it underground.

I didn't want to press the issue because the owner was walking away with so little profit, but now seeing all the work it took to get that property up and running he would have been happy at $0 profit just to get rid of the liability (still was a very profitable deal for me though!!).

Even with access to the furnace I am still very nervous,  I have listed my concerns below  (FYI house is 800 sq ft on crawl space in SE Michigan)* Attic is vented and there is no insulated room around the furnace* Attic is supposed to be cold...how does that work with a furnace in it!!!

As for changing the lease terms, you would be hard pressed to add something to it until it is up for renewal.  

As I continued to overload myself with as much information as I could, I started to hear all the fuss about wholesalers getting cracked down on for "unlicensed brokerage activity", and it gave me cold feet.

Russell Brazil Guy Harriss My second suggestion which I was going to make earlier but didn't was to BP-Stalk Russell as he's the resident splash of cold water on multi-family in MD.