How much does WiFi cost?

Usually no. If you get it from your house (wireless router for example) or from a restruant (like McDonalds) they won't charge you. But if you use someone else's wireless connection (like another person or some money-grabbing business), they might charge you. I think Nintendo has a list of businesses/restruants that won't charge you for using their wireless internet connection on their website. ------------------------------------------------------------------------------------------------------------