Rich-list couple Tenby Powell and Sharon Hunter have put their multi-million-dollar property on the market.
The edgy modernist Westmere house, once visited by Prince Albert of Monaco and his glamorous wife, Princess Charlene, has a $20 million price tag.
Mr Powell told the Weekend Herald it was a great time for owners of big houses to go to market.
He also said the family were downsizing as "it is a very big house and our son has just moved out and our daughter has just started boarding".
The couple are giants in the New Zealand business scene. Sharon Hunter started PC Direct at the age of 22, before selling it in 1997 and setting up investment company Hunter Powell with her husband.
Agents Graham, Ollie and Andrew Wall have the listing, with exclusive viewings of the hotel-like house now being conducted for the market's wealthiest buyers.
The house, designed by architect David Ponting of Ponting Fitzgerald, has big entertaining areas, floor-to-ceiling glazing and an infinity swimming pool which visually merges seemlessly with the sea, the Walls said.
The property has an outdoor dining area with sleek designer furniture to match the house and a big oblong-shaped fireplace. Glazed internal balconies, five bedrooms and multiple living spaces are other features.
It also has what the Walls called "the ultimate underground 'man cave', with a bar, huge television screen and pool table." The house is on a section of more than a quarter of an acre, sprawling across two sites, amalgamated for the one building.
The 739sq m residence has a 30m beach frontage lined with pohutakawa. An artificial stream flows from the front alpine-style garden, through the centre of the house and beneath the main stairs, emerging at the pool overlooking the beach.
"It's said to have been the biggest in-situ residential concrete pour in Auckland at the time it was built," Graham Wall said. Overseas people might buy it, he indicated.
Rawene Ave house
• Beachfront Westmere house expected to fetch $20m
• That could make it NZ's most expensive sale this year
• Two levels, 5 bedrooms, vast entertaining areas
• Basalt-lined internal and external walls
• 'Ultimate underground man cave'
• Artificial stream flows from front garden to pool
• Stream passes beneath the house, emerging in hallway