Closet shelves messy

Going to sell my 900 sq foot condo built in the mid 1960s

Looking at the closets.

The smaller shelves come out easily enough to do something with.

There are some with contact paper that is stuck on very securely, but they are dirty.

There are others that have contact paper over that old contact paper and is coming off. Looks like melting in places.

Some are bare wood.

The long closet ones would be a pain to take out to deal with.

Most kitchen ones, and most kitchen drawers have some no stick fabric.

The wood is solid.

Any ideas how to proceed?