What should John's agent do if Mary offers to buy John's house for $560,000 instead of the listed price of $540,000?

The agent's responsibility in this scenario is to communicate any offers received for the property to their client, John. This duty is fundamental to the fiduciary relationship between a real estate agent and their client. When Mary presents an offer above the listed price, it is crucial for the agent to inform John so he can make an informed decision on how to proceed.

By telling John about the offer, the agent ensures that he is aware of the current market interest in his property and can decide whether to accept the offer, negotiate further, or explore other options. Open communication is key in real estate transactions, and an agent who fails to relay such an important offer could jeopardize their client's interests.

In contrast, actions like ignoring the offer, discussing it only with Mary, or solely negotiating on behalf of John without his knowledge would not fulfill the agent's obligation to represent John's best interests. The correct approach here is to keep John informed, allowing him to guide the next steps based on this updated information.