What is the value of a Remington 12 gauge vintage shotgun?

The Remington Model 12 Sportsman came in semi-auto or pump configurations, and were made from 1984-1986 (vintage?). The auto is booked at $300 in 100% condition and $150 in 60%. The pump from $275 to 140. (Add 10% if it has Rem-chokes).