Hi, Diana! Have you thought about maybe reserving a villa at one of the Disney Vacation Club resorts? The resorts are open to anyone, and have a very deluxe feel to them. For a party this size, you could do a two bedroom villa or one of the treehouse villas located near Saratoga Springs Resort.
Depending on dates, the two bedroom villas can start at about $675 per night. They include a full kitchen - including dishwasher, microwave, full sized refrigerator, oven/stove, all of your pots, pans, plates, and utensils. You will also have a washer and dryer, which can be a huge money saver if you are paying for luggage to be checked in on the plane! We also like to stock our refrigerator with drinks, snacks, and some breakfast items so that can also be a money saver.
The master bedroom has a jacuzzi tub, a king sized bed, desk, and television. The second bedroom has two double beds, another bathroom, and a television. There is also a fold out sofa in the living room.
Deluxe resorts start at about $350 per night per room, but suite rates that would accommodate a party of five or more can run anywhere from about double that to upwards of $2000 per night, depending on when you go and what type of accommodation you are looking for.
For a more economical deluxe experience, I find Animal Kingdom Lodge and Wilderness Lodge to be slightly less expensive than the monorail resorts - the Contemporary, Grand Floridian, and Polynesian.
I hope you have a wonderful vacation!