Hi Don,
We try to follow as many sales as we can, shows, auctions, dealers price lists, this message board, etc. We usually average them in while considering the source. We will use a leval below an auction price for high value items, figuring that the bid is what one person is willing to pay. We use an asterick with the letter value when there have been few sales, sometimes only one. Once the market has been tested, we will remove the asterick and adjust the value. A good test is that we have been on the money on 90% of the chips in the clubs' annual auctions. Each year we try to review all of the 14,000 chips and make the needed corrections.