From that pic alone, it looks pretty decent. Really if you are able it is of course best to go see it in person before bidding, because when these trucks sit for quite a while on these lots, parts tend to get stolen off of them. However, parts to these things are pretty readily available from multiple sources online, so missing parts really is not such a huge concern most of the time either. A blown up engine could possibly be your worst problem, but even that, I have seen those engine for sale for about $700.
So far I have gotten lucky, and both of the trucks I have bought from GL that I have gotten home so far (the third one I'm still waiting on the EUC paperwork) have only needed new batteries, and my M813 needed a new protection control box on the firewall because someone stole that. But I was able to order one of those online and had it within a week. Most of the time, these trucks are in pretty decent shape. They just simply reached their serviceable life span, and the government decided to park them. Many of them were running fine when parked, so all they really need is some new batteries, and some typical maintenance that a long term stored vehicle would need, and you are good to go and up and running!
And as others have said, typically I have seen trucks in that kind of condition, with a hard top and winch go for upper $2000's to mid $3000's. If you don't have to have the winch, you can get one for quite a bit cheaper a lot of the time. I really wanted one with a winch, and it took me a while to score one within my price range.
But yeah, it is a very addictive hobby, so if you are the kind of person to get addicted to things, plan on expanding your driveway real soon