Here is a little tip especially if you have the Disney Visa (you get 6 months no interest). I will have the cruise paid off prior to the 75 day mark so about a month out (or after booking excursions to know that cost) I sit down and figure out what I know I will spend. Last time it looked like this:
Tips (for 2) - $225 - agree with above that you will want to tip more than "required since the service is so good
Pics - $50
Souvenirs - $200 (I get something for several family members)
Palo $75 - one brunch and one dinner plus tip (for one adult)
Spa - $350 - I love to splurge on this on vacation
Drinks - $75 - a few drinks at dinner throughout the week
Excursion - $200 - did castaway rays, a Disney excursion in St Thomas (did my own in St Maarten so that doesnt go to the onboard account)
Coffee - $35 for the week (at Cove Cafe)
This adds up to over $1200. So a couple of weeks prior to sailing, I call Disney and purchase a "gift" for myself of OBC of that amount. That way you get the no interest for 6 months and you have the OBC waiting for you when you board. YOu will still have to put a CC on file but only for the charges if you go over the amount above (which I always do by a little bit
)
This give me a little more time to pay off the extras if I havent saved the whole amount prior to the trip.
Have fun!