how many people are you taking. what kind of ameneties are you expecting. Are you going to get a package with flex features or just the bare bones. Your plans on things you would like to do would help. Are you going to get length of stay passes. annual passes , or 5 day multi pass tickets. these thing will all effect how much it costs.
My recommendation is sit down make a wish list of all the things you would like to do. to help you do this purchase one of those tourist books at your local book store. Here is a list of some of the books I have: Frommer's Disneyworld, Disneyworld for Idiots, Everything you want to know about disneyworld and greater orlando(my favorite), and the official guide to disneyworld. These books will help you find the dining experiences that are appealing to you, as well as , discriptions of the different disney resorts, price ranges are also discussed. Also , in this book is information about universal and sea world, and some of the smaller attractions in orlando.
let me tell you from our experience. We are a group of 4 that stayed at the carriebean beach. We had few frill. Only ate one hot meal a day. breakfast and dinner usually ate in room.
our ticket package room/tickets for 6 days cost us roughly 2200
we had 1400 dollars in spending money between us and still came back with about 450 dollars. We are very frugal people we don't spend when we could do with out but we always have fun.
When you write back with a kind of iteneray we might be able to tell you more accurately our opinions of what it might cost.