I agree w/MVR. I would get a 3rd party to get truck you want to buy. I got a 3rd party (a Hummer dealer to inspect it). My truck was being sold at a different dealer in town.
If you can't find a Hummer dealer to inspect it, I would recommend using an independent inspection company.
I've used
http://sgs-ebay.sgsauto.com/
SGS inspection company is very reputable and is recommended through eBay.
The inspector come out to the location of the vehicle and thoroughly inspect and take pictures for you. After the inspection, (which can take up to 2 hours), the will create a file for you and send it via email.
Everything from the condition of paint, to the interior, ...they take pics of everything so you know what you're potentially buying.
The price is very comparable to a Hummer dealer. PLUS, SGS sends you pics...
all the Hummer dealer, all I got was a 2 page PPI summary.