Hmm, well when I'm going to get my BP at a mom and pop reptile place a few towns over, I'm gonna look for things like alertness(looking around, checking things out), tounge actively flicking about, checking for a tight grip when I handle the BP, checking for signs of RI(wheezing, bubbling mucous stuff around nose and mouth), signs of a bad shed(pieces of shed left over and not helped off yet...usually points to careless keeping), check out the environment the snake is being kept in to see if the husbandry is good, see if there are any mites visible, and finally I'll ask to see if they have any feeding records so I know it's a good feeder. That's what I'm gonna have to check out when buying from a reptile store. But if you're at a reptile show, I doubt you'll have to be that curious and inquisitive. You can usually trust to get a good pet from some good breeders at reptile shows. But those are still good things to do when looking for a nice baby to take home. Better safe then sorry, if you ask me.

Good luck, and have fun.