Using the same agent to represent both buyer and seller is 100% legal, as long as all parties are made aware and agree to this BEFORE signing a contract. While it is legal, that doesn’t mean that it will always be in your best interest.
The biggest problem with using a Dual Agent is that the agent has a legal duty to get the best “deal” for the seller, and the best “deal” for the buyer at the same time. This goes beyond just price; there are nuances in how agents write up and negotiate the contract to best protect their clients. A Dual Agent might aim for the middle ground to try to be fair to both parties. In addition, if the transaction starts to go sour, the agent may be feeling more pressure than normal to “keep the deal together.” When you have an agent that only represents you, that may give you more “walk-away power.” For example, a Buyer’s Agent might say to a Seller’s Agent, “If your Seller won’t fix the roof, my buyers will go buy another home.”
However, there are many advantages to using a Dual Agent. First, the negotiations go much faster and with less misunderstanding. By taking one person out of the loop, communication flows much better. The listing agent does has first-hand knowledge of the home and about the seller’s needs. Another advantage is that many agents will offer a financial discount, usually to the seller, when representing both sides.
Remember that you, the client, are in charge. You get to pick who your agent is, and you decide if you are comfortable with Dual Agency. You should be a little bit cautious if an agent exerts extreme pressure on you to agree to Dual Agency against your wishes.