The man cave had an AV system for Mr Higgins' sport-watching.
"[My husband] was a great rugby fan, he wanted to watch rugby down there so that's what the man cave was built for," Mrs Higgins said.
"He never got down there, which was sad, that's really why I'm selling it. It was built for my husband's semi-retirement."
She moved back to Palmerston North after her husband died, near where her daughter lives.
The man cave is the only feature not on the main level of the house.
The home was built to blend in with Taupo's shoreline. Its profile is low, its cladding echoing the raupo (bulrushes) occurring naturally.
Valued at $1.49 million, and selling by negotiation at more than $2.5 million, 57 Victory Drive has had a huge amount of investment poured into it, beginning with the involvement of a premier architect.
"We gave the brief to architect Richard Goldie," Mrs Higgins said.
"He did a lot of research. We picked him up from the airport, but he wanted to walk back there so he could take photos of the lichen, grass and lampposts. He wanted to get a feeling for the environment."
Called Still Waters, the home was profiled in Home NZ in 2009. The magazine noted how impressed with Taupo's grasses Goldie was.
"This gave rise to the idea of mimicking that verticality in the home's warm-toned cedar screen, a gesture which makes the home beautiful to look at despite the almost windowless face it presents."
Mrs Higgins is particularly proud that Goldie's design has defeated the howling winds which can come off the lake.
"It has a courtyard with glass floor to ceiling. It's sheltered from the southerlies and the westerlies. The courtyard faces north. The courtyard is like another room, if the wind is blowing you still get the lovely view.
"It's very private from the road. We don't look on to any other houses, they don't look into us. Our focus is the lake and mountains.
"It won an architecture sustainability award because in front of the garage it's all grassed, but under the grass is gobi blocks."
The absorbent blocks aren't the only environmental aspect to the home. Solar panels and double glazing help with the underfloor heating.
The home comes with five bedrooms, three bathrooms and two en suites on more than 1000sq m of land.
Purchasers have an option to secure a further 1000sq m lake-front section next to this property, from which they can gaze upon the mountains and go hiking, biking or boating.
Mrs Higgins is actively involved in the local Hospice charity. Mr Higgins is commemorated by Manawatu Golf Club's Arohanui Hospice Michael Higgins Memorial golf trophy.