I've had the same question as the OP. I do like watching these shows cause some of the design ideas they come up with are really cool, lot of 'em I've already built into my RV. I'm a former county planner where I administered and enforced zoning laws and can say that there is nowhere in the county which I live (Whatcom County in Washington) where they would be legal to live in. Maybe Montana, Idaho, Nevada or somewhere remote it might be ok. They aren't built to building code standards and they don't qualify as RV's so they essentially have nowhere to go except the driveway they are built on. I actually live in a "tiny" house. We live in a 345 sq ft. park model, so we know the attraction of downsizing, plus we own it and our lot so have no payments. We are in the one RV park in the county allowing full time living in park models, which are probably the original tiny houses.