Final answer:
The listing agent must provide the agency disclosure form before engaging in any substantive discussions with potential buyers at an open house to clarify the agent's role and protect confidentiality.
Step-by-step explanation:
At an open house, the listing agent must provide the agency disclosure form before they engage in any substantive discussion about the property with a potential buyer. The agency disclosure form is a document that clarifies the agent's role and responsibilities to the buyer, including who they represent in the transaction, whether it's the seller, the buyer, or both as a dual agent. These disclosures help to ensure transparency in the transaction and are required by law in many areas to be given early in the interaction, often before any confidential information is exchanged.