LOL she doesn't do snakes and handed you the key? That has to be the most rediculous thing i've ever heard of. Why on earth would you be working in a pet store when you fear and won't be able to give any information whatsoever on the snakes to the customer. These pet store stories never cease to amaze me.

As for your setup it sounds great, and if I were you I would follow the previous posters suggestion and find a good breeder (their are tons on this site), and buy your ball off them. This ensures the snake is disease/parasite free and is eating well. Even better is that most of the proffessional breeders have ball's way cheaper than ones in pet stores, excluding the shipping of course. Good luck and im sure you'll love your snake.