I did some sums recently and it was $1,100 for car plus insurance plus parking for 14 days . Uber is looking at roughly $5-700, depending on whether you can use Disney buses or not, for the same period. Obviously depends how much hopping around you do as well.
This was when Disney wasn’t charging for parking at their hotels. I got the car pretty cheap too.
With Disney now charging, it will probably be more expensive for a car.