We just booked an airport shuttle from hotel to LAX, for our family of 6 and all our luggage.
We could have got an Uber that seats 6 for about 30% less, but as far as I can tell there is no way in the Uber app to know how much luggage they can take. I don't Uber often, so didn't want to get stuck with charges/fees if we had to cancel, or be late because we needed a second car for our luggage.
How can I book an Uber large enough for my family and all our luggage?
Uber offers guaranteed seats but no guarantees about luggage space in addition. If you want to be sure you can fit in 6 people plus reasonable luggage, you should order the next size up, which is the "Uber Max" minivan for 7+ people. However, this is not available in all locations.
The other option is to book an XL, call the driver immediately, and check if they can fit you & your luggage. Most drivers are quite good at luggage Tetris, although even they can only do so much to bend the laws of physics; if they decline, you'll need to eat the cancellation fee, but it's usually only $5 or so or even waived if you cancel quickly enough.
