Sissy-Based on what you're describing your agent is not following license law. 1. In order for the agent and/or broker to represent both buyer and seller in a transaction, both buyer and seller would have to agree, in writing to dual or designated agency. This assumes that the agent has a buyer agency agreement with the buyer and has a listing contract with you as the seller. It's possible that the agent doesn't have an agency agreement with the buyer, thus should only be representing your best interest in this transaction. 2. As for asking you to sign an agreement that would restrict you from listing your property with another agency, to my knowledge there's no state contract condition that would require such. The standard exclusive right to sell listing agreement (WB-1) does have an extension provision in it that states any offers received during the course of the listing would be a "protected" buyer for a period of 1 year from the end of the contract. What this means is the buyer who's offer you currently have would be covered under this contract for 12 months if you and the buyer would come to agreement on a purchase. This condition, however, doesn't restrict you from entering into a listing agreement with another brokerage/agent.
I would suggest your contact the agent's supervising broker and have a conversation with them. In addition it's always wise to hire an attorney to give a legal opinion. I am not an attorney, just a broker who feels that based on what you've stated, you aren't necessarily being treated fairly in this transaction.