We forgot to add our son to our OKW reservation for last Sept. He is a CM and lives in Windermere, but will often come over to pick us up or ride the bus with us. Plus with F&W, he could have a magic band to charge to Mom & Dad's account (CMs don't make that much). I asked at check in to add him and the CM at the desk suggested to just add him as a day guest (meaning no Magic Band) because it would mean cancelling and rebooking the reservation. (Seriously, Disney should be able to change the guests in the room with cancelling and rebooking - but we're talking Disney IT, right?) Cancelling and rebooking means a messed up points account most of the time. So add your guests now and not at the desk when you check in. And if you are getting the dining plan, suck up the extra cost or drop it all together. And put that money on a Disney gift card (and use that to pay for your dining).