Supply and Demand
Like any other market, the prices on coins, currency, & collectibles is based on supply and demand. Supply and demand in simple terms says that I can have an item that there are only 5 known in the world, but if there is only one buyer, chances are it will sell for very little because the buyer has so many choices. It might not even sell at all! Converesly, I can have an item that 10,000 are available and we have 100,000 people that want these items, it’s a good bet we will get good money for this item and quickly. In a nut shell, that is supply and demand.