At only 120 square feet, two is company - and three is really a crowd. The house is too small to meet building code minimum standards. It's a vehicle, reports CBS News correspondent Jim Axelrod.
But it's got all the comforts of home, and plenty of storage space.
Shafer is at the forefront of the "small house" movement - a school of thought that less is more, especially in a recession.
"This house, all decked out with plumbing and heating would be about $50,000 if we built it for you," Shafter said. "But if you built it yourself, it would be about $20,000."
According to the U.S. Census, the average single family house in America is a little more than 2,500 square feet, meaning you could fit 21 of these into one of those.
"I think they're amazing," said Elizabeth Randol, a possible buyer.
Right now, Randol lives in 1,500 square feet, but she finds tiny very tempting.
"You buy the house, no mortgage and no utility bills," Randol said. "So any money that you make goes right into your pocket."
And she's not alone. Shafer's been criss-crossing the country with his tiny house in tow, teaching workshops on the art of building small.
When he pulls over and posts where he is on his Web page, the small house draws large crowds.
Like the houses themselves, sales are still small. But interest is growing, and Shafer is finding a new use for an old sales pitch: good things come in small packages.