very, very good find. It's an antique caucasian rug, absolutely worth what you paid. the wear is probably less wear than it is oxidation. dyes are fixed with mordants, which are acidic to wool, and often deteriorate it at an accelerated rate - especially darker colors/dyes which are sometimes made with metal.

I am sure they did. If you want to find out real market value, you should list it on ebay for sale. Otherwise, it is whatever the buyer is willing to pay. In an antiques store, it could be many more times what any rug dealer would sell it. as private party, you are not going to get top dollar.