What to know before going to a reptile show

I'm in the process of setting up a terrarium for my first crested gecko- 24x18x36, so plenty big enough- and if I finish up by the 22nd, I found out there's a small reptile show that day only a half hour from me. I've been doing a ton of reading about gecko care and terrarium setup on here, so I feel pretty ready in that regard.

I've never been to a reptile show, though. This is actually going to be my first time owning a reptile. Is there anything I should know going in? Any red flags to look out for when picking out a gecko? I'm really excited about the idea of being able to pick out my new pet in person instead of just looking at pictures online and hoping for the best with shipping, but I also want to be smart about it and know if there are any common pitfalls to look out for.