A movement toward tiny apartments and tiny houses is growing in America.
San Francisco is currently considering allowing apartments as small as 150 square feet.
Many cities, like New York, now allow the so-called micro apartments that are only about the size of a parking space.
And some people are living in tiny, stand-alone houses.
Sarah McNair of Manassas built a tiny house for her Master's thesis at American Military University, part of the online American Public University System.
"Well, you're in what I call the Great Room," McNair says as she shows the house to ABC7. "Everybody laughs at me, but this is essentially the living room."
The house has a main floor with seating area, kitchen, and bathroom.
And a loft above has a queen-size air mattress.
The tiny home movement in America has grown since the housing bubble burst.
And McNair's home is green. It's fueled by a mobile solar panel and propane, with Energy Star appliances and recycled furnishings.
The entire house is just 150 square feet, compared to the average American home of almost 20 times that size.
And another big difference. It's mobile.
It's attached to her dad's truck, like an RV. Some tiny homes are stationary.
It cost McNair $20,000 plus appliances, about the price of a nice car. She'll be selling it, however, to pay back her loan from dad.
"Eventually, I would like to build a whole bunch of these and build a Tiny House bed and breakfast," McNair says. "someday."
For the record, McNair got an "A" on her thesis.