Mike, 70's is not what you would even call a vintage engine, but it depends on what kinda shape she's in. Before you make an offer you want to make sure she has spark and compression. Coils and condensers have a tendency to go bad sitting for 25+ years. Figure a water pump because over time the rubber impeller will fall apart and possibly having the gearcase resealed. If she needs an ignition, carbs cleaned and rebuilt along with a water pump you can figure a dealer charging you 2-300 min.If the engines needs this stuff she's worth 150 bucks. If she's been tuned and ready to run she's worth 300-350.
