The carts were usually the fun part of building any sort of a ride; Phineas was always creative with the coloring and such. Ferb didn't think the white and red stripped carts were too bad but...he could do better. Maybe after it's set up he add something.

His train of thought was cut short and he glanced back at Hermione. A moment to think and then he shrugs. Usually the clean up takes care of it's self. Hopefully it'll happen here too...if not clean up was all on him.