Much like using a real estate agent to buy or sell a house, it is highly advisable to hire a domain name broker to manage the process for you. If you hire a quality broker, they will be able to do the required research to get a deal done, have the negotiation skills to get a good deal and manage the escrow and domain name transfer process.
The process can be time consuming and complicated. Hiring a trusted professional to broker your domain name will free up time, help you get the lowest price if you are a buyer or ensure that you get the highest price if you are selling a domain name.
Your domain broker works for you. The broker should set your expectations, keep you informed and guide you through the process.