TOPIC: Determine value of like new 1977 Glassmaster Boat

I recently bought a 1977 Glassmaster 17' w/115 Evinrude from an estate. It had belonged to an eccentric old gentleman who was known to buy things and never use them. I was told this rig has never been in the water and from the looks of it, I believe that. He kept it in a garage, so the paint, seats and top are still in very good condition. He did start the motor and run it on a water hose once a rear. He even kept up the Texas Parks & Wildlife and license plate sticker until his death last year.

I intend to sell it but have no idea of the value. Can anyone out there help me determine it? Thanks!