I love to look for deals. It's my first cruise, so no booking discount or OBC, but I will be getting $805 back from Costco, plus another $212 that I'm getting in rewards for booking with Disney Visa. I put it on the card, then turned around and paid the card in full. I figure I saved over $1,000 that way, though the Costco gift card doesn't arrive until after the cruise. The bright side of that is if I spend too much on vacation, at least I'll get some groceries at Costco to tide us over.
I also used frequent flyer miles for airfare for the 5 of us. That saved me another $1800. It took a while for me to fly enough for work to earn the 125K miles it cost, and I sure hated to see the balance in miles go to 0.