As a lifelong resident of the northeast, I can say as a fact, that there are no rust issues of any significance here, period. The claim that the propane tank needs to be replaced is BS, BTW. Every tank looks like that, here in salt country, after a decade. In my neighborhood, Dodge vans of that vintage are long gone for one simple reason. They have rotted into the ground. On a scale of 1-10, given the age of the rig, I would give the undercarriage an 8.5. Overall, the vehicle is well graded by the surveyor. It's in fair condition, with a lot of small, yet poorly done repairs, and a long list of deferred maintenance items. You have been give a long list of well documented issues that you can easily place a fair value on (new tires, radiator, shocks, etc...) and use as negotiating tools. The shoddy repairs might not be what you think. Some folks just have very little in the way of skills, and a need to try to fix anything they can. I have a buddy with a fairly new fifth wheel trailer that looks like hell, since he tries to fix everything and shouldn't be allowed near a hammer or screwdriver. As a retired snowbird, I see this fairly frequently. I Can't tell you what's best, but that van wouldn't scare me in the least, and certainly doesn't have rust issues worth worrying about.