Legal Question in Real Estate Law in California

You are not legally required to use an agent. Even though you have agreed on the price, there are certain disclosures that are required by law, and there are different options on how to set up the transaction. So, you should either do careful research on those topics, or pay for advice regarding the transaction.

If you have agreed terms of a sale, not just price, there is no need for an agent, but as Mr. Dorfman correctly notes, there are important disclosures, as well as other legal "i's" to dot and "t's" to cross. So it might be worth paying an agent an agreed flat fee to guide you through all that. At a minimum, get a current copy of Nolo Press, "For Sale By Owner" or similar legal guide with forms. If you are going to have any "rent to own" terms, or if you are going to "carry-back" any debt on the property, you had best consult with a lawyer -- it will be a few hundred dollars that might save many many thousands in taxes and litigation down the road.