Sometimes big projects start small. In Auckland's seaside suburb of Mission Bay, former triathlete Scott Unsworth knocked down the fence between two apartment buildings he and his wife Hildegard owned — and realised the land around them could hold something far more ambitious than extra parking.

The result is a planned boutique wellness precinct at Stay Mission Bay, the couple's serviced-apartment operation on the corner of Patteson Avenue and Marau Crescent. The vision goes beyond guest-only extras: think saunas, hot and cold plunge pools, health and fitness facilities, nutritious lunches and dinners, and possibly a rooftop bar — with doors open to the wider public, not just those sleeping there.

The Unsworths are no strangers to building brands. Scott founded swim and triathlon label Orca in 1995 after injury ended his racing career; by the Sydney Olympics in 2000, most triathletes were racing in his gear, and the company later dressed the New Zealand team in Athens. He and Hildegard — whom he met around that era and proposed to in Greece — ran Orca from Hong Kong, Auckland and London, turning down outside money including an approach from New Balance's owner before striking a licensing deal that let them keep global ownership.

Back in Auckland, they spent roughly 12 years assembling seven titles around the Mission Bay property, funding each purchase with equity and income from the last rather than a big backer. The precinct today is two buildings: the ivy-clad Patteson, remodelled under Hildegard's interior direction into Hamptons-meets-tropical style, with eight serviced apartments topped by a four-bedroom penthouse sleeping 13 that rents for around $2,000 a night. The three-storey Marau adds five more beach-bungalow-style apartments from $250 to $600 a night. Property sources value the near-2000sqm corner site at more than $15m — money the couple would rather pour into their wellness concept than a five-storey apartment block.

Their ambitions don't stop at the fence line. Through Stay Luxe, they exclusively manage more than 40 high-end Auckland properties (from $2,000 to $20,000 a night) and list nearly 100 more luxury homes and lodges nationwide, plus run the Savoy, a 52.5ft power catamaran that once carried Miley Cyrus. International expansion and a second charter boat are pencilled in for next year.

For travellers, this is one to watch. Mission Bay already draws crowds to its beach, promenade and views along Tāmaki Drive toward Rangitoto, but accommodation there skews residential. A wellness precinct that welcomes day visitors — sauna sessions, a swim, a healthy lunch by the water — would give Auckland's eastern bays a proper spa-and-stay option within easy reach of the city centre. If rooftop-bar rumours prove true, sunset drinks over the harbour could become the suburb's best booking.