We have always done it for less than $3000. I find excitement trying to figure out how to do it and make sure its done!
We have a family of 5, we stay during spring break, stay on site,and eat at the parks(except breakfast)
Rm=$850 week
Tickets=$923.80 (no park hopper) or $1119.80(w/park hopper)
Food=$600 ( we bring snacks, but still have icecream each @park and popcorn to share) we bring bottled water usually never buy any drinks at parks this saves alot of $. we eat at Counter Service I go ahead of time look at the menus at the parks, pick where we would like to eat those days...I already know what everyone would prob. order so I know how much each will cost before we leave. This year we will prob share some meals because we ended up throwing away food because we couldn't eat it all
Souv=$200.00(sometimes the kids have more $ if they have saved their B-day $. If we go during spring break my ds and dd and myself will have just had our b-days so we have alittle extra to spend on souviees.
That leaves us with $231.00 sometimes we use it sometimes we don't.
We drive down and its 12 hours, we don't eat fast food in the car on ride down I make sandwiches, cold chicken, chips, fruit etc. Then we have the snacks for the week for the park. We do eat on the ride home but that never costs more than $30(taco bell)
We eat breakfast in the room before we go down I buy cereal, muffins, poptarts, fruit,etc. I usually start 2 months out and buy along with my weekly budget for groceries and just put aside(look for coupns and specials)
As for gas on the way down...We have a money jar that we put change in or a dollar or two in daily this usually covers our gas. We have an SUV and a van but husband likes to drive the SUV he says its more comfortable to drive the van would be less in gas but whatever makes dh happy.

When gas are higher we have had to put about $60 into the gas fund.
We have eaten at TS at least 1 time each visit too we have the extra left over ($231) So as a family we decide if w want to or use it for dinner or more disny stuff!
When we have been during the less peak times this has been about $600-$800 cheaper but w/ the kids in hs its too hard to take them out of school.
We actually like going during spring break...if you are there at rope drop you can get everything done you want..We were there last year when the parks closed when they reached capacity and we never waited more than 15. Thanks to my disney planning and RIDEMAX!

The kids don't really mind getting if they were at school they would getting up earlier.
I could prob save alot more money throughout the year but we always tend to decide to go about 3 months before hand so it doesn;t leave alot of time.
my kids love to shop but have always managed to stay w/in their budget and be perfectly happy, they dont know that they are missing out on some of the ts meals because they have never done it. My oldest dd is very picky and wouldn't enjoy those meals and it would be wasted $. My husband and I prob would but he is a chef already and can make wonderful already so we eat well when we are home. We don't go to WDW for the food!