Brendon Poole and Nikki Cliffe couldn't find a first home they wanted to buy in Auckland - so they came up with a plan to get others to pay for it.
But there's a catch: their grand scheme came with a ballooning budget that escalated from $2.7 million to close to $6 million.
The Auckland-based couple, a structural engineer and marketing manager, told their story in the latest episode of Grand Designs NZ.
Their plan was to build their first home in Ponsonby, a four-level apartment complex including commercial and retails areas as well as a second apartment to rent out and help get others cover their costs.
"We were looking around for a normal house, I guess the same as everyone else," Poole told the show's host, Chris Moller.
"But the areas we really wanted to be in, you're looking at $1.2-1.5 million for a do-up that you'd have to spend at least $400,000 on.
"We just went, 'We can't afford that'."
Instead, they discovered Vinegar Lane, a mixed use development including commercial, retail and residential areas on the old site of an old vinegar factory in Ponsonby.
They planned to build an "urban sanctuary ... a beautiful, relaxed, calming space" inspired by their favourite holiday destination: Bali.
It included two retails spaces, a commercial level, a second apartment, their own penthouse apartment, and a rooftop garden and lap pool with 360-degree views of the city.
Their plan was to rent out the retail and commercial spaces and second apartment, as well as the garden bar for corporate functions, to help pay off their massive mortgage.
"We can live in it, enjoy it, but also it's a business. We've got all these other levels to help us pay for it," explained Cliffe to Moller.
She said design was the key to making their compact development worked.
"Design has been such a key. It's all about creating spaces inside smaller spaces, like building the outside on the roof. Hopefully we won't feel like we're too enclosed."
Poole agreed: "It's really efficient living. You can live up top, work down the bottom, your shopping and everything is all around you.
"It gives you more time to exercise and do things outside of work instead of sitting in cars bumper to bumper."
But the budget quickly escalated as the project got delayed, ballooning from $2.7 million to $3.5 million, and then to $5.7 million.
Poole told Moller it ended somewhere around the $6 million mark.
The pair also had a baby - son Cooper - during the project's five-year creation, holding things up even further.
Despite the hold-ups, Moller was full of praise when he saw their finished apartment with views around the city.
"It's huge, it's vast, it's wonderful," he declared. "I can't quite believe it."
But the pair revealed there had been some hair-raising moments that could have sunk the project.
"We've had a lot of luck," Poole said. "It could easily have turned the other way and we would have been in a lot of trouble."
The pair also revealed that it wasn't over yet. They're still finishing the lower levels, the ones that would help them pay their $6 million construction costs.
"The journey goes on. We've still got the challenge of getting them tenanted," said Poole.
* Grand Designs screens on Three on Tuesday nights.