You may go without an appointment just make sure you arrive early. Also, make sure you bring two proof of residence such as insurance or utility bills. If you are going to apply for the Real ID you will also need two proofs of identification such as Passport, SS card and/or birth certificate.
You can but arrive early. Also, fill out your renewal application online and get an confirm number. Bring in any supporting docs. Will go much more quickly if you do.
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