Welcome to Tiny Homes, an idea that is more popular with minimalists than with neighborhood associations and zoning boards. We'll point out the fun parts. You'll have to check out the logistics and legalities - but this one has been in place since 1959.
Go just a little bit bigger than a tiny house on wheels (THOW) and get a lot more room. Get something built in 1959, and it's probably grandfathered in. Go far enough out of town and find out what it's like to have plumbing reminiscent of 1859. Out by Mt. Index, there's a tiny house for sale for $49,950. That's more than most modern tinies that are on wheels, but the 320 square foot cabin also comes with an 80 square foot bunkhouse. If you wanted a tiny house and wanted the noisier folks to sleep in another building, you can do that. Instead of a shed roof, or a conventional pitched roof, it's a bit of both that gives a lot more ceiling clearance on one side but still protects the other side from weather. The metal roof effectively becomes metal siding, which can be handy the closer you get to Stevens Pass. Outside is that other luxury, the 80 square foot bunkhouse that could also be the main bedroom if you didn't want to climb the steps every night. Outside is also the outhouse, because where else would you put an outhouse? There's also a rainwater collection system. That may be trendy now, but they both may be hold-overs from when there wasn't much more of an option.