Value Please

[Cal44]

I am trying to get an idea for a couple that own a 1975 S coupe, white/tan. They sent a bunch of pix and the car appears very straight. Car resides in a very dry climate. Dash is not good and old guy painted the trunk black.....hmmmm. They think is worth 12.5K, that is what they offered it to me. I on the other hand think something quite different. Paint and interior look good. Any opinions? Thanks.