Gaia Series 106: Renovation you won't regret

In Yokohama and Tokyo, families take on hidden renovation costs, while one firm tests a flat-fee model to bring clarity, and hope, to an industry many no longer trust.

In Yokohama’s Kohoku Ward, on the edge of Japan’s second-largest city, the Iizuka family are preparing for a new arrival. Their two-bedroom flat, just 52 square metres, has served them well for the last five years. But with a second child due in August, they realise the apartment is no longer enough.

“When we learnt a second child was on the way, we realised this place would be too small,” they say. Space for storage is tight, and even simple things such as fitting a pushchair at the entrance have become a problem.

The family looks at buying a new build. But prices in their area have surged, rising 24 per cent over the past decade. The average cost of a new apartment in Kohoku now stands at 82.64 million yen (S$720,000). Their plans quickly change. Instead of buying new, they decide to purchase a used flat and renovate it to suit their growing needs.

The floor plan they choose includes a wide entrance, a walk-in wardrobe, and room for their expanding family. But once construction begins, so do the surprises. “When we opened the walls, we discovered asbestos,” they recall. The removal alone costs another 120,000 yen. Then the screens turn out to be too old to reuse. Piece by piece, costs climb.

Originally quoted at 11 million yen, the final bill reaches 13.746 million yen. That’s a 25 per cent jump, and higher than they were prepared for.

Across Japan, families are facing similar stories. Renovation budgets rarely hold. One survey cited in the episode notes that final renovation costs often come in 50 per cent higher than the original estimate. As demand for used homes rises, so too do stories of shock invoices, unexpected delays, and an industry that many homeowners say feels like a black box.

In response, some are trying to open it.

Groove Agent, a Tokyo-based renovation firm with around 100 employees, is testing a new approach. Instead of pricing each job with long estimates and site visits, they offer flat-rate renovations. The idea is simple: charge based on the size of the home, not the guesswork of what's behind the walls. Clients choose materials like flooring or wallpaper from curated catalogues, with transparent costs and optional upgrades clearly listed.

“We know the demand for such clarity is strong,” says project lead Ayumu Noda, who designed the scheme after spending a year testing different materials and price structures. “This allows them to create a home they truly want, which is where I find the real satisfaction in this work.”

One of the families trialling the system is the Masudas. They buy a 41-year-old flat in Tokyo’s Katsushika Ward for 14 million yen. It’s 12 minutes from the station by bus and needs a complete overhaul. Their dream is simple: an open-plan kitchen and living room, where their children and pets can roam freely, and they can cook without worrying.

“We really cannot take our eyes off them,” they laugh, recalling how even their dog causes mischief. “Being able to see them while we cook will make life much less stressful.”

They meet the Groove Agent team in Minato Ward to finalise details. They choose glossy white tiles: “easier to clean,” they’re told and a deep blue accent wall for the bedroom. Later, they decide to swap out the standard gas hob for a sleeker glass-top model, paying 40,000 yen extra. By the time they finish adding touches, their final quote hits 13 million yen. But it’s within budget, and the rules are clear.

Or so they think.

When they return to inspect the renovation midway through, they notice something odd. “Those spots there and there still bother me,” they say, pointing at the ceiling. More than 15 large holes have appeared. These were hidden by panels before demolition began.

“They were opened when the block was first constructed,” the team explains. In many renovations, such surprises are covered by contingency funds. But the Masudas are unsure: will the flat-rate promise hold?

Groove Agent calls an internal meeting. Director Kazuhiro Nishimura floats a solution. “We could all chip in bit by bit, like insurance,” he says. They agree to set aside reserve funds in every project to deal with unknowns without sending homeowners extra bills.

In the end, the Masudas' quote stays flat. On handover day, the family steps inside their completed home. The kitchen and living room are now a wide-open space. The entrance has been rebuilt to easily fit a pushchair. The holes are sealed. Their final bill: 12.92 million yen.

“Firstly, the price came in within our budget,” they say. “That was a big relief. In Tokyo, being able to buy a home for less than 30 million is something to be very grateful for.”
But while some renovation stories end well, others turn painful.

In Tokyo, Ms Yamada, a woman in her seventies, recalls the day a team of men showed up uninvited. “They rang the bell and said, ‘Your roof looks quite damaged.’” They offered a free inspection, climbed up, and returned with photos. Before long, she signed a contract of six million yen for roof work.
Later she found out the job should have cost half. “Signing so easily that day is my biggest regret,” she says. When she tried to follow up, the company had closed. Several of its staff were later fined under construction laws.

In Shizuoka, some contractors are trying to undo the damage. Munehito Nagasawa runs a roofing company that inspects homes using drones. He explains each issue carefully, shows reference prices, and never asks clients to sign on the spot. His firm charges a modest 5,000 yen for an inspection, compared to the tens of thousands extracted in scams.

It’s part of a growing movement. Led by Takanori Meisho, the “Roof Pro” network is building a database of trustworthy roofers, each one licensed and willing to publish their rates online. Meisho believes the only way forward is visibility. “Unless roofers connect directly with customers, fraud will never disappear.”

For long-time roofers like Mr Kobayashi, joining Roof Pro is a chance to future-proof the trade. “I suppose safety and reliability, though it sounds basic,” he says when asked what he wants clients to see.

By July, Groove Agent’s trial flats are finished. Roof Pro’s listings are growing. And somewhere in Katsushika, the Masuda family now cook dinner in their bright, open-plan kitchen, keeping an eye on their children and remembering the time their dream home was just bare concrete and blueprints.

“I think what we value most is transparency and reassurance,” they say. “That sense of safety is what really matters.”