Try

http://gsaauctions.gov/gsaauctions/gsaauctions/

Or search for a local government surplus auction in your area.

I work for a utility and it is considered a government agency and we sell stuff on the SC Gov auction site often.

Most things are well maintained and are sold due to age or mileage on vehicles.

I bought my old work truck dirt cheap a few years back after getting a new one. It was only 4 years old with a 100,652 miles on it. I knew it was in perfect shape and I got it for $1800!

Here is a link that might be useful: Gov. auctions