What's a used one worth?

I found a guy selling one used and I'm thinking about getting if he doesn't want to much for it, it comes with one complete truck and a lot of parts (almost enough to have another truck) 2 full sets of tires.

I heard they discontinued the MT2 so are the parts interchangeable with teh MT Spec 3.0 and Mugnam NX (I think that's the name)

Thanks,
JB