Being a real estate broker, I always recommend hiring a real estate agent to assist in the transaction, and paying a commission that is appropriate for the amount of time and effort and money that is reciprocated by the agent. Some agents spend thousands of dollars and months of time making sure that every available buyer that is looking for a home in your area has the ability to see your home online, or via open houses and print advertising. That is basically what every seller wants, the best ability to have a buyer see their home and make an offer...
The next part of the equation is the ability to Close the transaction, and this is the part of the sale that sellers never seem to understand or appreciate. Every real estate transaction is different, and the myriad of issues that arise during the transaction, from inspections, repairs, appraisals, lending/underwriting problems, escrow, and legalities - this is where the real estate professional earns their commission. From the day that a contract is executed, until the day that is closes, there are no easy escrows, with the lone exception being an undervalued property being sold to a cash buyer...
The way that a real estate professional earns their commission, is that they sell your property for the highest possible price, and get the property to close escrow. If you don't believe that your agent is worth their pay, then interview others. In order to test this theory, hire a flat-fee broker, put the property in the mls, and offer a typical 3% commission. You will spend time wondering who is seeing the property, why there are no offers, and what other agents/buyers are thinking. If you have the right agent, then all of those questions are answered, and your property sells for the highest possible price that a buyer will pay.