Not necessary.
They are typically quite busy, so I would recommend an appointment however it is not necessary.
Appointment isn't necessary but recommended, more so if it's you plus a friend. They will accommodate seating you next to one another.
Agreed they accept walk ins but honestly I call 30 mins before I want to come in, they make the appointment and then I don't have to wait!
You can walk in and they try their best to fit you in. But they are always busy so I highly recommend making an appointment. Even if you just call the morning of.
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