Auckland airport from Britomart station by train and bus transfer at Puhinui station - transfers every 10 minutes. Total cost $8 - compared to $70+ via taxi or rideshare. Similar travel time.
(Normal trip cost is $5.40; the $8 included a new AT Hop card. It was also Santa Parade day and central Auckland was gridlocked. Uber was quoting $122 to get to the airport - and it would have taken 1.5 hours....)