For estimate appriasal and values, please go to the Blue Book Publications Official Site. Many of my spec descriptions comes their site as well as Washburn, but I do not list estimated value. Check out their other databases as well. An online subscription is not expensive and it has loads of interesting information. I have used it for many brands other than Washburn.
Early Models (including B and Scavenger Series)
Force Series (bass)
Mercury Series (bass)