Can't really offer much of an opinion without seeing and playing the guitar, but maybe you could take it to a couple of music stores and see what they would offer you on a trade-in. Needless to say, you 've have to find one you trust, but visiting a few can either give you an idea of what it's worth on the market (maybe even check comparable guitars they have in stock) if the offers are consistant or let you know who would try to rip you off if one or two really low-ball you on price.
I had a classical that I had hand-made while I was in Japan and a friend who played classical claimed it was a very good one. After about 10 years I decided to trade it in for something — don't remember what — and discovered, since I hadn't played it for a while, that the neck was pulling loose from the body. I got next to nothing for it, but I can guarantee that whoever got it after the neck was reset had a nice little box.