We use a regional coupon website to make couponing easy. I save $20-30 a week. Twice a year, we shop the freezer and pantry until it is minimally stocked. I usually do it in early August (in case hurricane season brings power outages, we don't lose much.) and then again in January.
Using a Target Red card to get 5 percent off of gift cards is a good idea. You can give each child a gift card as their souvenir budget.
If you have a wholesale club or car club membership, compare their ticket prices and options to
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We have also been cleaning out unwanted household items. Not just because of the trip, but to de-clutter outgrown clothes, repurpose space, etc. since this is "found money" it goes into the trip.
Cut soda and flavored drinks out of you diet. We save a lot of money by only drinking water - at home and when dining out.
Have children participate in saving. They will think twice about requests if they know it will take away what they can spend on vacation. They can also request Disney gift cards from family members for holidays and birthdays.
My husband's workplace matches the first $5 he puts in a Christmas Club account. Free money and easy automatic savings before he gets his check. We only put in what they match.
A garage sale could also provide income for the trip.
If your grocery store has fuel rewards, use them! I saved $7 on my last fill-up. I don't buy an item just because it has fuel rewards, but will buy an extra if it is something I use and has additional rewards. We also get rewards for every dollar spent, no matter what the item.