I have been to WDW 10 times and have used AAA for 7 of those times. It's funny because some years, I get a better deal just going through Disney. However, my experience has been about 10% off as a whole. For example, if my package price [room, tickets w/ park hopper, water park option] through Disney is $3000.00 - then my AAA price may be $2700.00. One year, I think 3 years ago, they cam out with a special after I had booked with AAA and I emailed my AAA
travel agent and she re-booked my trip with the special, which was
free dining. I also make all of my ADR's. Even though you book through AAA, you get a confirmation number and you can go on the WDW website and check your reservations. I make my ADR's and they are all attached to my resort reservation. I then do the online check-in as well.
Along with a hotel discount [most of the time], you get some additional perks through AAA. I don't take advantage of them all but some I do. They give you a AAA Diamond Card that you can use for certain discounts. As an example, you can get 20% off for lunch or 10% off of Dinner at Fulton's Crab House at DTD, 15% off at Earl of Sandwich and House of Blues, 10% off at Bongo's at DTD, 15% off at Ghirardelli at DTD, 10% off at World of Disney at DTD, etc. You get discounts on recreation activities, tours, spa treatments, etc. You will get a booklet with all of the info directly from AAA travel.
As I mentioned earlier, we never use all of the little perks you get with AAA. Bottom line for me is if the price for the hotel and tickets is significant, then I will use them. We just went to WDW 8/2-8/11 and we used AAA. I believe the savings this year was about $200.00. Some years, the price from Disney and AAA have been exactly the same -

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I hope this helped. By the way, if you contact a AAA travel agent, they could do everything via telephone or email. That's what I do. The materials from Disney are sent to AAA and then they [AAA] mail it to me at home.
Good luck. Let me know if you have any other questions. Send me a PM if need be.
Jose
Norwalk, CT.