Pit Market Trading
Buyers
You can buy one unit of the commodity during each trading period. The number on your card is the dollar value that you receive if you make a purchase. You will be required to buy at a price that is no higher than the value number on the card. Your earnings on the purchased card are calculated as the difference between the value number on the card and the price that you negotiate. If you do not make a purchase, you do not earn anything in the period. If you mistakenly agree to a price that is above your value, then the trade will be invalidated when you come to the front desk; your card will be returned, and you can resume negotiations.
Example: Suppose that your card is a 9 of spades, and you negotiate a purchase price of $4. Then you would earn $9 - $4 = $5. You would not be allowed to buy at a price above $9 with this card.
Think of it this way: it's as if you knew someone who would later buy the bond from you at a price that equals your value number, so you can keep the difference if you are able to buy the bond at a price that is below the resale value. You are buying low and selling high.