There's a long-term parking lot at the boat stop for $12 a day. Overall, the trip was great for families. The boat tickets are indeed expensive, as are the island's shuttle bus. But my wife and I loved it; the kangaroos alone were enough. The views from the key parking spots were spectacular. Kangaroos were everywhere. Back at the pier, buy some bread and sit by the roadside; a kangaroo will approach you. It wants bread, but it's best to feed it leaves.