Is there anyone on the Coast who does this?
Sometimes the honest answer is that the nearest is in Christchurch or Nelson, and the quote should say so with travel in it. NovaPay asks locally first and tells you when it has had to look further rather than quietly widening the search.
What if my flight is delayed?
Most operators track the flight and adjust, which is the main advantage over a taxi booked for a time. Give the flight number rather than a time so they can.
Is the price fixed?
For a booked transfer it usually is, agreed before the day. Ask whether waiting time, tolls and after-hours are included, since those are the common extras.
Can they take a group with luggage?
Yes, but the vehicle has to be matched to it. Say how many people and how many bags, because six adults with ski gear is a different booking from six adults with cabin bags.
Do they have child seats?
Many do, and New Zealand law requires appropriate restraints for young children. Ask for them when booking rather than on the day, and say the ages.