What action would violate a real estate salesperson's duties when representing only the buyer?

Disclosing the highest price the buyer is willing to pay would violate a real estate salesperson's duties when representing only the buyer because it compromises the buyer's negotiating position. In a fiduciary relationship, the agent has the responsibility to act in the best interests of the client—in this case, the buyer. Sharing this sensitive information with the seller or their agent could undermine the buyer's ability to negotiate a favorable purchase price and effectively give away a strategic advantage during the transaction.

By keeping the buyer's willingness to pay confidential, the agent can help ensure the buyer is not pressured into paying more than necessary. Meanwhile, disclosing seller's motivations, market conditions, and neighborhood crime statistics can be helpful and relevant information that does not directly harm the buyer's negotiating power, thus falling within acceptable behaviors for representing buyer interests.