I have a 1990 Guild d-30 that I was considering selling. The guitar has cracks in the finish that look a lot like the ones in this picture. They are on the front and back. What kind of reduction in value do these cracks cause?
I wouldn't discount it at all ... let someone play it, and let 'em chisel you down a few a bucks. In truly vintage guitars finish crazing doesn't reduce value by much, and if your guitar sounds like what a buyer is wanting, it shouldn't reduce your value by a whole lot.
It's called finish checking. Normal for a vintage guitar. For a 1990 model, not so much. I would expect a mild reduction in value, but not too much.