A Commission Agreement for Sale is used for one-time showings of real estate so a Realtor can show a home to a prospective buyer and be paid a commission. A One Time Showing Agreement is a commission agreement signed between a buyer's agent and a seller for specific named buyers.A OneTime Showing Agreement form is a legally binding agreement between the buyer's broker and the homeowner listing the property for sale. Florida Realtors' Revised Exclusive Buyer Brokerage Agreements are Now Available. – Florida Realtors® released new showing agreement forms on Tuesday. A listing agreement is a contract between homeowners and brokers that legally establishes how a realtor will find a property buyer on the seller's behalf. Yes all Realtors working with buyers will have to have a signed agency agreement before showing homes. Showing Agreement (SA-3x). Exceptions to the agreement requirement are open houses, or contacting the listing agent directly to request a showing.