Hi,
I would ask her which species it is and then start looking for good caresheets and such as specific as you can get.
Try and get some good clear pictures of it if you cannot inspect the animal itself beforehand.
Also just ask the general questions - how is it with handling. what and how often does she feed it etc.
If you have only handled BP's before they definately move a lot quicker until they settle down.
But find out what kind of milksnake it is and then go from there.
dr del