Thanks. The city are being xxxxxx LOL. Nobody has given me a SPECIFIC reason. The are hinting that it's because of building condition. Well HELL!! I know that, I'm not trying to heat it to 70F all day. I just want temp heat for keeping pipes alive, and working in there on cold days. I spent about a dozen years doing HVAC service. What needs to be done. Pressure test and city approval on the gas piping. It is not extensive. Unused stub in the basement for a never installed kitchen range, an outdoor quick connect barbie style, an upflow furnace in the basement, and a corner living room free standing "millivolt" heater where the old wood stove once was. The upstairs heater got water and blown insulation stuck to it, and I bet I can tear it apart, pressure wash, and repaint and use it. I doubt anything needs replaces, as all components are "underneath," gas valve, blower, etc.
The furnace, probably needs ducts cleaned. They are all accessable, as basement walls/ ceiling wallboard all removed and will be left that way (cost.) Thanks for the offer, too early really to know. I doubt there is any damage to the furnace per se.