Check out this tiny home that has been built in a backyard and from repurposed materials so it only cost about 1500 dollars to build. While it is small, only 10 by 10 it seems to suit the builder and lets him live a super simple live without major expenses.
While I am not so sure that I would want to live in such a small space I do think it would be neat for a guest cabin or even some private space for a college student home for the summer. It would also make a great office or man/lady cave. He has rain water collection and he does his cooking outside. A lot of this is probably illegal but I guess not till he gets caught and the tiny house may pass as a shed.
Exploring Alternatives tells us how he built it and what kinds of materials and where he sourced them from in this video.