The techs seem to be on vacation a lot so I suggest at least calling ahead
No appointment needed but highly advised to call ahead to make sure their computer is working. It was down all weekend and someone from the state was supposed to look at it today(Monday).
No appointment, but would call to make sure that they can take you in. Last time they told me the guy that does the inspection comes in at 10am, but once I was there they were super attentive and i was in and out.
Thanks! Your answer is awaiting moderation.