I really don't think you should sneak the snake into the house. If the landlord finds out that you are housing animals that are not paid for, he/she can claim you have breached your lease and kick you out and keep your security deposit. Sneaking the animal into the house could have consequences that you haven't thought of.
You should wait till you are out on your own to get one if you can't stand to pay the pet fee. And if by then you don't really have any desire to get a BP, then you've saved yourself some hastle and quite a bit of money.