Utility
Neither the Toyota 4Runner nor the BMW has a marked advantage with respect to seating capacity.
The Toyota 4Runner is likely a better choice than the BMW X3 with respect to transporting cargo, especially if you often need to carry a lot of luggage or big pets.
The Toyota 4Runner outpulls the BMW X3 by a big margin.
Dimensions
Your wallet will hurt more every time you fill up the Toyota than the BMW X3 because of its bigger tank.
The BMW X3 and the Toyota 4Runner compete for the same parking spaces.
Convenience
You'll most certainly have to take the BMW X3 for a fill-up more often than the Toyota 4Runner because of its tank size and fuel economy.
Cost
The destination charge is a standard charge for transporting the vehicle from its point of origin to the dealer. It costs approximately the same to get the Toyota 4Runner to the dealership as the X3.
There honestly isn't much of a difference in gas mileage here, but if you must know, the BMW is a bit more economical than the Toyota 4Runner.
The X3 isn't much pricier than the Toyota when it comes to MSRP.
Handling
With their comparable turning circles, the Toyota 4Runner and the BMW X3 likely handle about the same into and out of tight spots.
Drivetrain
The Toyota 4Runner's engine is substantially bigger than the BMW's. Bear in mind that bigger engines may use more gasoline than smaller ones.
Torque equals pickup, and the Toyota will have picked up and gone by the time the BMW X3 finally gets moving.
Comfort
Taller drivers will substantially enjoy the extra head room in the 4Runner's front cabin compared to the X3.
The ampler interior dimensions of the BMW X3 make it more spacious for your passengers than the Toyota 4Runner.
Warranty
The basic after-sale protection that comes with the Toyota 4Runner isn't quite as generous as the BMW's.