Wherever you want it to. They can go all the way to your building. I always send a text to the driver after confirming the trip and tell him exactly where within the resort I am.
The only trouble I have with this at SSR is if I am staying in Congress Park. The app often thinks I am at Disney Springs since it is so close, and then it tries to tell me where at Disney Springs the pickup will be. A few times, I've had to walk toward the carriage house a little to get far enough away from Disney Springs to fix that issue.