I've heard people say to bring a baggie of detergent and dryer sheets, does that mean that they don't offer detergent in the laundry room and you HAVE to bring your own? I don't mind paying for it there, I just don't want to have to pack it. Also, I know everything is paid with your KTTW card on the ship, but do they have change for the machines or do you HAVE to bring your own ahead of time? Thanks