When selling your home or business through a real estate broker should you try to negotiate the commission?

I am selling my hair salon first then plan to sell my home as I am getting married and moving to the US from Canada. When I chose a broker and he sent me a copy of the listing agreement, he wants me to initial saying that he has exclusive rights (vs. Multiple Listing) for one year. Also, when we discussed it initially, I told him the price I wanted to start at, he verbally suggested a lower price, and has already written his price suggestion on the listing agreement which I have not yet signed. I've since gone on his website and see my property already listed at his price. History: I had him appraise the business about a year ago (because someone was interested in buying it and they suggested him as the appraiser and I agreed) and the potential buyer decided not to purchase at the appraised value. If I were to list at the price the realtor is suggesting, I wouldn't get the appraised value after his commission. What should I do?