It was many years before she was able to turn one of her designs into reality, but when she and Michael found their land at Omapere, everything fell into place.
"We'd been based in Auckland - I'd been there all my life - but we knew the Far North. Michael had gone to school here and we both knew the Hokianga. When we decided to retire, we knew we wanted a place on the west coast with sea views."
They had checked out the South Island but found it too cold. Then they visited Omapere to see what was available. The real estate agent showed them this block and they were, as Marianne puts it, blown away.
"We saw it, fell in love with it and decided to buy it on the spot."
Michael suggested that Marianne design the house and she was delighted that he trusted her with the project. She had, over time, consulted many books on architecture to get ideas and she knew that with this view, all the rooms had to face the sea.
"Michael gave me carte blanche so I just started at one end and added on until it was finished," she says.
The brief they gave themselves was fairly straightforward. Having lived in a villa in Auckland they both liked high ceilings, and they wanted to feel comfortable and spread out in spaces that were pleasant and relaxing to be in.
Because friends, children and grandchildren had to be accommodated, Marianne designed the house with four bedrooms and four bathrooms, and added an indoor swimming pool.
"I don't do cold water, and I wanted to swim all year round," she says.
She drew up the final design on graph paper and gave it to an architect, who turned it into an architect's drawing. He added more angles than were on Marianne's original plan. "My graph paper was a bit limiting in that respect," she concedes.
Low-maintenance and high-quality materials were also on the wish list, so the house was built with brick, a marine-grade Colorsteel roof, copper spouting with concealed down pipes, cedar fascias and detailing and broad timber decks. Inside, the couple used Stainmaster carpets, tinted windows, stacker and folding doors, diffused light and air conditioning.
The swimming pool and its surrounding living area has been the focal point of the home.
"When the children and grandchildren came they were in it all day - we used to pull them out to feed them and pop them back in again," Marianne says. "It's been like a second living room. The older ones would sit around the table out there in the evenings listening to music, and it became a real social hub."
The whole house is well set up for entertaining with a big kitchen and plenty of room for guests to spread themselves out.
"We had 25 people here for Michael's 70th and everybody fitted in easily."
It's a testament to Marianne's design skills that the spaces work so well for large gatherings of family and friends.
"The house glows when people are here eating and drinking and enjoying themselves," she says.
