A One Time Showing Agreement is a commission agreement signed between a buyer's agent and a seller for specific named buyers. Can a realtor sign a sales contract without a complete listing agreement?In real estate, there are 3 types of listing agreements that any home seller can sign. You don't have to sign anything, and you don't have to use a realtor. Does this mean that brokerages can only have one agreement with the buyer? The new rule prohibits most listings from saying how much buyers' agents are paid, removing the assumption that sellers are on the hook for paying both agents. The requirement is to enter into a written agreement, prior to showing properties. This agreement is designed to inform buyers that they are responsible for paying their own Realtors if a seller chooses not to cover the cost.