Question on what i should pay for a 1973-1974 dart sport

Location needs to be kept in mind. In the NW corner of Illinois, these cars are impossible to find. Rust has crunched them. I remember in the mid 80's it was a task to find a 78 - 79 Volare with minimal rust. Right now, in my location, these cars are either restored and they are asking $$$$$, or they are complete parts cars, and seldom seen. Therefore, with a little lower 1/4 rust, so - so interior, this car would not be a hard sell for 4k.