I bought my Deuce, listed as "Running Contition Unknown" sight unseen through GL. The GL listing pictures showed a decent looking truck, it had troop seats, near new tires (the spare has never been on the ground!), air shift front axle, and 16k miles on the odometer. I bought strictly on my gut feeling it should be a good truck.
I put a posting here and on the MV mailing list asking if anyone had a contact for a truck mechanic at the base where the truck was located. I ended up contacting a mechanic with considerable experience with M35A2s. He checked it out for me, got it started, drove it around and told me I had a good buy. After all the paperwork cleared, I drove 230 miles to the base with my tools, engine oil, gear oil, diesel fuel and brake fluid to pick it up. Checked the fluids and vital points, the mechanic met me there to help me get it started (it had one bad battery), then I drove it about 35 miles to a friend's place for a more thorough checkout. From there I drove it home without any problems, with the wife following in the family van, just in case!
My number 1 suggestion is to find an on base mechanic to check out your prospective purchase BEFORE you bid, then you know if you are looking at a jewel in the rough or an expensive pile of crap. The places I contacted wanted from $450 to $900 to pick it up on base and deliver it to my home, a distance of about 230 miles, so I saved a BIG crapload of money by driving it home myself. BTW, it had 3/4 of a tank of diesel it it when I picked it up, so I didn't even have to pay for the fuel for the trip home!
I repeat - find an on base mechanic to check your truck out beforehand, drive it home yourself, and save yourself a bunch of money. You'll need that extra money for the truck soon enough!