political items are very collectable and especially JFK items. Kovels have a poster of Jfk 1960 valued at $1,150.00 but nothing in any of their books on car top signs. Your sign would appeal to people who collect signs and political item’s and Wisconsin people. Is it all metal? I can’t give you a value because none are listed in books. I would assume that this is rare. How many people would have a car top sign this large? You only see these at parades. I would guess in the thousands. It might be metal is worth more then cardboard???? Just not sure