Barn find dart

Hey all, looking to purchase my first mopar. Came across a 67 dart 270
2 door. Car was in the back of an old barn. Guy says it has been sitting there for approximately 40 years. All the glass is good, has very minimal rust and original paint, trim all intact. Interior rough but all there. Has a 273 v8 auto transmission. He says make an offer and drag it home. I have no idea what to offer for a first timer. I don’t want to offend him. What would be a fair ballpark price to start at. Thanks
I would figure and price it as a parts car. Anything better is a bonus.