4. John Hancock Tower
Sale price: $660.6 million
Size: 1.76 million square feet
Location: Boston, Mass.
Boston's John Hancock Tower might just represent everything that went wrong with the broader U.S. commercial real estate market. Relying on massive amounts of financing, an ambitious New York City-based investment firm scooped up New England's tallest office building in 2006 for an eye-popping $1.3 billion, betting that Boston's office rental market and commercial property values would continue to remain red hot. What they never anticipated, like so many other real-estate speculators, was the precipitous decline in property values and a spike in the nation's unemployment rate to above 10%, which drastically weakened demand for office space across the country. Unable to service the debt load, the property was sold in a foreclosure auction last March for less than half of the original purchase price.
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