Tiny home aficionado Derek Diedricksen built this off-the-grid, 8' x '8 "reading" cabin in Vermont for just $300. He was able to keep the price tag so low by using recycled parts. The front deck was made using an abandoned fence wall and free 2 x 4's.
The wall of windows looks like it could have been made with salvaged materials as well. As for the corrugated roof, my friend Craigslist is loaded with it, but, even purchased new, it's still very affordable roofing material. For more information about the cabin, which, by the way, is called The Rock Bottom, visit Inhabitat.