Hi hat's mom
What has worked well for us and many families is to set an amount ahead of time that your child is allowed to spend on souveniers and then make sure they know that when that is gone there is no more. It is really neat if you can give the money to then in Disney dollars. How much you give them depends on thier age and what you expect them to buy with it. Will they have to buy a t-shirt if you want them to have one or is that a mom and dad treat? What about snacks? Even that extra candy bar that they don't need? Also think about if you will give them total freedom or not in spending their money. I always reserve snack veto power so I can forbid a icecream cone 10 minutes before dinner time.
Their age also will determine how you give thte money to them. For a teen, giving it all to them at once might be ok. For a younger child, I would divide it into days and give them a part each day. What they save from one day can be spent the next. If they find someting that they really want, they can wait enough days until they have that much money. Often they decide by then they do not want the item anyway. Another rule that works well is that I will NOT carry any stuff they buy in the parks. We can go back at the end of the day, or they can carry it. DS does not like to carry stuff so this too cuts down on inpulse spending.
AS far as buying ahead, many people do this but I find DS still is attracted to the stuff in the stores. There are outlets in Flordia that you can get great prices at but I am sure someone else on the board can tell you more about this.
They have evey Disney item you could imagne at WDW. Everything form a dollar staw to 10,000.00 paintings. And everything in between. One thing is that the quality on most stuff is very good.
We have already bought t-shirts on the sale on disneystore.com for our trip this year.
Sorry this is so long. Good luck and happy shoppping.'
Jordan's mom