First 80 psi in the tires is pretty normal.
Am I,correct in assuming that your 19G is an ex-Cruise America rental?
If it is: it's probably seen a lot of "careless abuse"; from folks who didn't know better...
The stove burner might just need a good cleaning. Try using a toothbrush on it. Take the time to get into all of the orifices...
The hot water heater: there are adjustments that can be made to them. It's best left to,someone with the background in it...
Freezer door? I got nothing for that one.
Giod luck!