I believe that the brokers do more than save you time. They ensure that your contract point status is accurate, market the contract, provide an intermediary service to facilitate negotiations (keeping the business perspective and coaching both buyer and seller away from the emotional reactions) and coordinate offer and paperwork until hand-off to the closing/title company.
The better brokers (our sponsor especially) can advise potential buyers and sellers about the program, the process, ROFR, market conditions and the like -- answering all of the many questions that arise. I appreciate their advice and market knowledge and that is what makes it worthwhile to me to find a good broker.