Fordy,
We bought two generators from Sears, both gas, we bought the extended warrenty, something, I wouldn't normally buy. Sears totally rebuilt both generators,TWICE, it was like gettin' 6 generators for the price of 2. We ran them, 12 hours a day, pumping the well in the summer. We really gave those poor things a work-out. We had planted a young orchard of about 70, various fruit trees, then the grapes and garden, and a cement pond that was drained regularly.
We had deep cell batteries and an inverter for electricity. On wash day the genie ran for the washer, the dryer was gas with electric to turn the barrel.
The thing about those little water heaters that come with a travel trailer:
You get a choice of, shampoo, shave or soap up and that's about IT. A five gallon water heater gives you about 5 to 10 minutes of HOT water max.
lacyj