If you collect very rare or finest known coins, figuring out what to pay for an item that you need for your collection can be difficult. Here is a real-life example of how I came up with what I believe to be an accurate value for a one-of-a-kind coin. The coin that we are going to use as our Coin Pricing Lab Experiment is the Finest Known 1860-C half eagle; an item that my firm recently handled.