The inspection also pointed out that the fungi growth should be checked once drywall is removed.I am concerned about mice infestation and likely damage to electrical wires and wood because of that.

For example, electrical is original from 1960, there is no central AC - heating it through baseboard heaters

For instance, one property seems to have an extra bathroom that is not listed in the county records.I plan to make some modifications, including removing a closet wall to expand a bathroom and taking out a kitchen island that contains electrical outlets and a switch.

But I think they'd be around $4,800 (conservative estimate).Seller is also claiming there are no common electricity at all- which is hard to believe, considering there's common gas, water and sewer. and most likely a common area electricity.

Based on not having water, roads, etc. you could still do a tiny home or RV space there if you put in electrical hookups and a septic tank.

I don't think you can raise the rent by installing it because most guests aren't going to be using it anyways and it will prevent guests from booking potentially because your price is higher than others.II say all this as someone who drives an electric vehicle. 

If you can get a heat pump and not have to upgrade your electrical panel or service to do this, that might be a cheaper option.

Electrical?

Electrical 3.

So, we have all these electric autos now right, they only need electricity to run.