I would guess that Government auctions should run the same. We've done some GSA auctions and a 52' Hatteras was one of them. Some random observations for you:
a. The item is REALLY and truly AS IS< WHERE IS. Don't expect anything to be working as it should.
b. Dirty? Yes, they don't clean anything and it might have been sitting out for a looooong time before the Marshalls release it for sale.
c. There's an Inspection date for these auctions. You'll have to take your wrench to see the boat with you. Take a water supply if they'll let you start the motors. Sometimes they do, sometimes not.
d. There is no warranty. None, Nada. Zip.
e. Title can a friggin nightmare. Try chasing a title down from the gummint.
f. If you buy something, don't give your money away until you have been totally satisfied about the how and why and when a title will be delivered to you. It might take many months, so check with your State DMV about how to use your boat while waiting for the title. If your state says, "no exceptions to the 30 day rule", think about whether the deal is so good that you'll be happy to park the boat for several months or so.
Other than that, these are great ways to save a bundle!!