Rule: Offer and Demand. Property: One is inversely proportional to the other. Outcome: If demand is high, prices for a certain good will rise. This effect will result in the consequence of demand going down due to the fact that a group of individuals doesn't perceive value in purchasing the good at the risen price.
In Monopoly, you can offer a player a certain amount of play money for a property he or she owns. The player might understand your need for such property and will not accept an initial offer. However, the offering player may raise the offered amount that might suit the interests of the player who owns the property.
