#10: Orange County, California
Nearly 30 percent of California homeowners are underwater according to CoreLogic's latest negative equity data, but four of the top 10 most expensive urban areas in the U.S. are in the The Golden State.
Orange County encompasses 34 incorporated cities, including Laguna Beach, Anaheim and Mission Viejo. According to Redfin.com, the median sale price of a home in Orange County was $375,000 in February 2012, down 6.2 percent from the previous year. (CBS News)