If you're interested in buying an extravagant home, the most expensive property on the U.S. market is a $75 million spread in Bridgehampton, Long Island, that includes a 25,000-square-foot main house, a nine-hole golf course, three large ponds, and a 3,000-bottle wine cellar. But million-dollar homes aren't just for people who like to golf in their back yards. According to a recent report from Harvard's Joint Center for Housing Studies, the number of owner-occupied U.S. homes valued at a million dollars or more increased by 170 percent from 1989 to 2001 (the total number of homeowners grew by only 21 percent); the average price of such houses now stands at roughly $1.7 million. A full 41 percent of the nation's million-dollar houses are in California, and five percent of them are within the Los Angeles city limits alone. But for concentration of expensive houses L.A. can't compete with Cambridge, Massachusetts, where 11.6 percent of all single-family dwellings cost $1 million or more—though $1 million buys only about 1,800 square feet in crowded Cambridge. There, locals say, "fancy starts at $2.5 million."
—"'Million-Dollar Homes' and Wealth in the United States," Zhu Xiao Di, Joint Center for Housing Studies, Harvard University