So here is the deal, I am trying to deal with an individual who owns a Sig 220 Sport with the compensator package. The gun looks to be in stellar condition, and all stainless steel (I think all sport models are). The question is how much to pay. If I offer him too little, I may never get another chance at it, and you know what happens if you offer too much. What is a fair price for a 90% NRA grade Sig 220 Sport with compensator, but without original case? Thanks in advance!