The GIS map designates it as a single-family dwelling, but the property is clearly set up as two units, with separate HVAC, electrical systems, etc.My main question is: Would it be possible to obtain a permit to legally convert it into a two-unit property?

Have a 1960s 30 unit single story motel where we are coming up on some end of life issues: the cast iron plumbing is disintegrating underneath bathrooms, radiators are starting to leak, electrical is in poor condition, and just today, discovered significant termite damage affecting multiple rooms.

Are bills like electricity and water something that's figured into weather or not a property is self sustaining?

It also seems to be more common in some areas of the country more than others (due to much older construction in the region, higher exposure to harsher climates, older electrical and plumbing running through the home, etc.).

They often do not seal it well outside and inside where the electric attaches.

I was ordered to remove the unit, which I used as a home office, and the expeditor who handled the project had the order reversed, and the apartment was converted to an office by removing a bathtub, and a stove and refrigerator in the kitchen.

Then you can have the specialist sub pull permits for their work under their license, plumbing, electrical, roofing, etc.. 

 But to be fair, besides people not being happy with those kinds of houses anymore, builders couldn't build them and make any money due to high costs of planning, permitting, sewer and water hook ups, electric hook ups, etc.Well, we do have this Tiny House fad right now, but can someone explain to me how these are any better than an old fashioned trailer?  

As of now utilities (electricity, water, gas and sewage) are a flat rate of $100 per unit which is tacked onto the rent.

Much cheaper to maintain and on the electric billand etc.I only build cabins in the woods though so again, the drainage would be the issue if you are more in a neighborhood or something.