The best thing to do is to go online and make an appointment for the location that you want to utilize. You can go down on Saturday and stand in a very long line. The earlier you get there the better.
Saturdays, they accept all walk in but during the week it's preferably appt but you can just go it may be a longer waiting time.
Yes, they have a line for appointments and walk-ins.
If you have all the required documents you could possibly walk in without an appointment. I did and it happened smoothly.
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