Most glass boats are good for 15-20 years before major overhaul is needed. Of course how it was stored and maintained means everything !!
Due to the age, a test for rotten structure wood is needed. The skeleton of this boat is made from wood and needs tested to be sure it isn't rotted. Transom and main stringers under the floor are the key pieces that support the hull. No matter how pretty it looks, you can't see inside the fiberglass hull to know if the main structure is still solid. Most owners are not keen on a buyer drilling holes to test for rot, so unless you hire a marine surveyor to test it out, I would look for an aluminum hull boat. While there can be some wood in an aluminum boat, it is easy to access and replace if needed. In a glass boat it can be a hard, messy and expensive job to replace that wood.