Set up appointment is for sure better, but they have walk in in case you need and there are no avail.
Go to Bay Co tax collector website, look for tag renewal and do it all online...you don't have to have an appt or go in to the office. He also has a kiosk, in one of the Publix', I think, where you can also do it
I just walked in, but you can call ahead and set an appt.
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