Everyone seems to have covered the husbandry, so I won't add to that. But I think the most missed oppoortunity for the owner of an adoptive snakeis to ask the previous owner a few questions.
1. What is he feeding the snake? If he's feeding it large mice and you try rat pups, the snake may not eat causing you to stress.
2. When did he feed the snake? Some snakes like to be fed at a regular time and will not take prey as easily as when they are usually fed.
3. How many days between feedings? Some young snakes like to eat every 4-5 days, others eat every 7.
3. What temps did he keep the snake? Ideally we should all keep our snakes at the same temps, but some don't. If he kept the snake at room temperature (yes, it done all the time from people that don't know any better), putting him into a 92 degree tank could shock the snake into not eating.
Good Luck!
Jim Smith