Such an arrangement has a built-in conflict of interest - you'll never be sure your trade was at market, and it opens the door to all kinds of nefarious activity. I've probably done 50 residential transactions the past 20 years, and every time the broker has double-ended the deal (representing seller and buyer), I've gotten screwed.
Maybe that strategy works in declining or soggy markets, but in ascending markets with lots of competition, it sounds good, but can backfire badly. IMO, better practice in hot market is to find the top producer in the particular market - interview, do extensive research, talk to anyone you can to get satisfied that your agent is the best in your marketplace (as measured by dollar volume, days on market, percentage completion, etc.) . Talk to the town - including mortage broakers, the broker office branch manager, contractors, insurance agents, etc.. Then engage the top broker on the sale of your existing home (if in the same market), and sign them on the purchase of your new property and offer them an off-book bonus if the purchase goes through (local laws permitting). In hot markets (like Chico), having the best agent in the area will aid in knowing your offer is above the water line, and that the terms of offer and acceptance are tight, and have a contingency plan if the offer is declined (backup position for instance).