Until now, hotels have been spared from waves of foreclosures that have rocked the housing market. But that could change this year, says Los Angeles hotel attorney Jim Butler. "It's like a water balloon and someone forgot to turn off the water. But it hasn't burst yet."

Occupancy and revenue are expected to plummet this year. About 36% of full-service U.S. hotels will lack the cash flow needed to pay their monthly mortgages in 2009 vs. 21% in 2008, says Mark Woodworth of PKF Hospitality Research.

Though it's rare for hotels in foreclosure to shut down completely, since debtors still want operating incomes, they are increasingly cutting back on services to save money. That means fewer restaurants will remain open and room-service hours will be cut. There will be longer wait times at the front desk and fewer bellhops working in the lobby.