You have a 72 and you need help with water and AC.
Don't sell yourself short. The AC is one 110 power line. No big deal.
If you are having problems with the AC unit itself it is unlikely that some yard bird will be able to help you much.
The water is not overly complicated. There are maybe 3 essential things. Pressure regulator from shore water, water pump and filters.
Get a service manual. Here is one here for 75 models.
Don't give up so easily.
It is not brain surgery. It is a travel trailer.