My parents live in a trailer (sorry, I am not classy, I don't say "mobile home"). You can get a really nice used one for under $15,000 here.
At the time, my parents' trailer was six years old. It has a master bedroom with a walk-in closet and private bath. The kitchen is eat-in. It has a nice-sized living room, two smaller bedrooms, and another full-sized bath. It cost them $20,000, which also included brand-new carpeting in every room that they got to pick out. It looks very nice inside -- actually, much nicer than mine. But, your theoretical cardboard box would look nicer than mine. I have the Ugliest Kitchen in the World.
Lot rent in a trailer park is usually $200-$300 per month and often (but not always) includes water and garbage pickup.
There are some very nice trailer parks here, but the nicer they are the more rules they have -- mainly this is just keeping up the lawn and exterior. You know, so it doesn't look like a trailer park.
Oh, and yes, I've seen one-bedroom houses. Generally they're pretty tiny and fairly old since it's been ages since anyone has built an 800 sq ft house. Here they are also usually in bad/iffy neighborhoods within convenient walking distance of seedy bars and junky used car lots.
I would never buy a condo. A condo is just like owning your apartment. Ugh.
-------------------- jen
"It's one of the most serious things that can possibly happen to one in a battle -- to get one's head cut off." -- LC