Data Points for Solar Housing -- $500,000 for a 650-Square-Foot House

Solar competition in Washington, DC. Some data points:

Houses are 750 square feet (though some say only 650 square feet)
Cost: $450,000 to $500,000 for material; labor was free
Price will drop to $300,000 if mass-produced -- this alone is quite a selling point
Only works when sun is shining; useless on cloudy days
Each team given $100,000 by federal government to compete
No one attended the competition except the participants and some press (see photo at link)

But at $450,000 (without labor) for a 750 square foot house.... I can't make this stuff up.

This contest has been running for years. Here's a link back to 2007 -- it doesn't seem we've made much progress if after a decade of doing this we are still in awe of a 650-square foot house that cost $500,000 in material (if mass produced, available from the Sears catalogue for "only" $300,000). 

I wonder if that includes those little squiggly lights that cost $10 a piece vs the 69 cent standard GE bulb?

Henry David Thoreau's home on Walden Pond was about 150 square feet, and was also solar heated.