There's a late 80s Cutlass convertible essentially mummified in a home made cover of tarps and packing tape. Been that way for years. Poor car is going to be worthless for the next owner.
Then there's my 1960 Thunderbird. It's always garaged and covered, but the cover is a very nice custom cover made for my grandfather's 1937 Cord, not the Thunderbird. It covers the car, but doesn't fit particularly well. It's time I invested in a proper fitting cover.