If you feel uncomfortable about a specific piercing studio you're considering, then leave, even if the price is right and the place seems clean and agreeable. It's possible that you've noticed something on a subconscious level, and your mind's trying to give you a hint.
The number one priority at any piercing parlor should be cleanliness and concern for your health. If the one you're considering is not sparkling clean and well-lit, bypass it for another that is. It's pointless to endanger your health just for a body decoration.
Any reputable piercing parlor -- from an earring kiosk to a full-service business -- will be willing to follow the local health rules, which can vary greatly according to jurisdiction. You should look for the relevant permits, which should be displayed openly, and be sure they're current.
