Final answer:
A broker operating under an exclusive right to sell contract is entitled to a commission only if he was the first to find a ready, willing and able buyer for the property.
Step-by-step explanation:
A broker operating under an exclusive right to sell contract is entitled to a commission only if he was the first to find a ready, willing and able buyer for the property. An exclusive right to sell contract gives the broker the sole right to sell the property, regardless of who finds the buyer. This means that even though Joe worked on the listing for a few months and was working with a potential buyer, Don, who is also a real estate agent and broker, sealed the deal with the buyer and is entitled to the commission as he found the buyer.