it can be as expensive or as cheap as your budget allows.
This is key (for all holidays and a lot of other things). It should never be driven by anything other than how much you can afford to pay.
All my holiday planning is based on that - work out how much you have and then adapt the holiday around it
I saw on an Orlando group that over a 14 night holiday they had spent £700 on ubers so cheaper than car hiring
Also dont assume actually that non resort hotels are cheaper - All Stars Music is actually a fairly cheap motel style resort hotel that comes with all the free travel aspects.
Universal Surfside Resorts are apartments that are good value for money as well
You should with some shopping around get that kind of price - British Airways over October half term (not sure if you have two weeks or could take time out) has 10 days flying out from Gatwick and back via Miami to Heathrow from 2.5k for flights and hotel
Disney cheap is 3.6, mid range 4.6
The Swan is 5k for 10 days for 4 - which is an amazingly located hotel for Disney - wouldnt need a car at all and could walk to Epcot and Hollywood Studios but does have a resort fee
Universal Surfside is 3k
October is a good time to go I have to say - consistently the cheapest I have found if you go outside of the week