I got this idea from someone else on here and it worked GREAT! She was 5 when we went last year for the first trip, and I saved a TON of money going this route...
before the trip I went to target and the
disney store and found little things on clearance... the same sort of things we would find in the parks like princess dresses, mickey/minnie dolls, little princess figures, new puzzles... and I brought little notes from the princesses and minnie/mickey, so every night when we got back to the hotel there was a fun new toy/dress and a note from her favorite characters inviting her to whatever we were doing the next day (cinderella invited her to CRT, Mickey invited her to Chef Mickeys.. and so on) It meant so much more to her because Cinderella gave her the puzzle or Mickey picked out the mickey&minnie dolls.. she loved it!! I think the most expensive thing I brought her was a princess dress from target she could wear to 1900 Park Fare, but most of the time it was just little things under $5.
everytime we walked through the parks and she would see something, literally all I had to say was "wow look at that! but lets see if Cinderella or Mickey leaves you anything special again tonight!" and thats all it took, she was so excited she'd just keep right on going to the next ride/show. To be honest I don't think we bought any new toys or anything in the parks, and yet she still came home with a whole bunch of new toys and dress up clothes! The other great benefit was that everything already fit in my suitcase going home, instead of having to try and pack a bunch of new toys!
worked great for us! :0)