If you're disabled simply walk straight in, tell someone immediately at the front and they'll direct you to a chair to sit. You'll be in and out with in 20 min or less
Yes, you can make an appointment either on website which is fully booked for next 2 - 3 months. The best would be to call and if they don't pick up just leave a message and they will call you back. They are good about it.
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