Yup, even the smaller ones like my dad's Class A have a generator in them. His is built on a 2006 Chevy 1 ton van chassis. Has a huge bed in the back, kinda small bathroom, dining room seats fold out to become a bed, plus there's the over the roof bed (all 3 are full size). One or 2 people could live comfortably in it for a summer, or winter if needed. Him and his dog would spend 3 months in Alaska, and part of a month getting there or returning. He was never in any hurry. While it's not as comfortable as hd's set up, it costs less to own and operate.I have a 100 gallon tank and a diesel generator. I also have solar on the roof. Yes 100 gallons of water will not last your entire lifetime. Yes you will need to dump tanks and get water. I can go a week without hookups showering every day if I'm careful.
I usually buy a month in a park so it's exactly like your house.