When I was looking to do the Waitomo caves black water rafting as a day trip from Auckland, InterCity provided the least expensive option by far. Getting to the bus terminal in Auckland was easy, the bus was comfortable and the driver had lots of information he shared along the way, and we only made a few stops.There was a little bit of a wait for the return bus but after rafting and eating lunch, there was maybe only an extra half hour of waiting. The return bus was waiting for us at the caves cafe so finding it was easy and the return trip had only on fuel stop. I definitely recommend using intercity for this day trip.