Capt Chris is correct...20+ years on a boat and things will be developing..in addition to the survey, take her our and see how she runs, and see how it sits in the water...scuppers significantly below the waterline may indicate a heavy core due to being wet...regardless, things like fuel tanks, fuel lines and water hoses and corroded wiring will be in your future unless it was done over by the prior owner...this goes for anytype or make of boat that old....but the GW hull should be solid.