WASHINGTON, D.C. (CBS NEWS) - In any organization as large as the United States government, some things are bound to slip through the cracks.
But how about an entire building? How about tens of thousands of buildings - all sitting empty at taxpayer expense.
No one has been coming to work in the USDA Cotton Annex building for some time. Just blocks from the White House, it's been vacant for six years.
It's one of 77,000 empty buildings the government continues to own and maintain, costing taxpayers $1.5 billion a year in electric bills, roof repairs, and other monthly costs.
What's more, a recent audit found that part of the reason the costs are so high is that the government can't keep track of what buildings it owns and what shape they're in.
The General Services Administration manages the government's real estate.
"We run into issues where people will say a building is in good condition and you go out and you take a look at it and there's no common sense definition that would say that that's in good condition," said director, Dan Tangherlini.
Tangherlini admits there are problems, but says empty buildings still need attention.
"One dollar of deferred maintenance generally turns into $4 of capitol reinvestment you have to make," he said. "So it's definitely a 'Pay me now or pay me a lot later.'"
There's an even bigger cost to factor in. By not selling these buildings, the government is missing out on the housing market rebound. Condominiums in the neighborhood of one deserted Washington D.C. school building have been appreciating for more than thirty years, yet the building has been empty since the 1980s.
David Wise is with the Government Accountability Office. He would not put a price on the building but agreed that millions of dollars would probably be a fair estimate.
The GSA says it is starting to move properties, using online auctions and building swaps for long-term leases.
Take for example one of Washington's crown jewels, the Old Post Office Pavilion. It has been leased to the Trump Organization for a luxury hotel.
Since 2010 the GSA has generated $200 million by disposing of more than 550 properties.
But there are thousands of buildings to go.
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