I learned today talking with some people about market places that you can trade derivates on the housing markets at Hedgestreet and the Chicago Merchantile Exchange. These new housing futures and options allow you to hedge financial risk associated with fluctuations in real estate prices. “CME Housing futures and options are cash-settled to a weighted composite index of U.S. real estate prices, as well as to specific markets in the following 10 major U.S. cities: Boston, Miami, New York, San Diego, San Francisco, Washington, D.C., Chicago, Denver, Las Vegas and Los Angeles.� I don't own any real estate in the bay area anymore, but if I did I might look into this.