What is the value of a Ford Econoline van 1962?

I'm asking for my uncle. Last year it was $650 now this year they are saying it's $2750. Something docent seem right with this and he wants to argue it with the people at the tax office. Also it's in about fair condition not sure if that helps.

You'd need to know the local tax laws. So-called blue books and such don't go back that far.

My favored rhetorical device in such situations: "One of you guys pay me $2750 for this van." Of course, they won't.