No personal recommendations I'm afraid, but something for you to browse through until someone else comes up with an idea.

City Rentals . A selection of apartments.
BKs Pioneer Motel Heard this one being recommended although it?s close to the airport. Free pick-up from there.
Centra Airport Hotel 5 mins. from airport.
Jasons if you want to research for yourself.
Motor Assoc. of NZ approved motels. Might be a bit more expensive, but should be good.
Howick Motor Lodge .
Serviced apartments . Expensive