Do you mean Gold Plated?

I think you mean gold laquered. I would say that you probably shouldn't get it relauqered, and if you have to, have it done professionally. DONT do it yourself, especially not with paint; it's laquer, not paint. And when a sax is relaquered, it can negatively affect the tone, playability, intonation and in many cases the vintage quality of the horn, so yeah, I think that would devalue it. I would (and I think many players) rather have an old horn with 10% of the laquer remaining than a relaquered, "pretty" horn. But don't strip the laquer either; that will affect the sax (for better or for worse), and you probably don't want any sudden changes in the horn's playability, so you should probably just let it go it's course.