Homebuyers in Cornwall are becoming more demanding. Long gone are the days when incomers wanted nothing more than a whitewashed fisherman’s cottage, and estate agents would advise anyone asking for something as flashy as a bungalow with a bay window to try Sandbanks, that enclave of footballers’ wives on the Dorset coast.

But is Britain’s westernmost county ready for property bling? That is the question being asked by Helen Blake and her boyfriend, Paul Stephens. The couple have put Blue Point, the house they have just built together at Gorran Haven, on the market for £3.875m. Set deep into the hillside, with an exterior of blue-tinted glass, the house stares out across this tiny harbour village on the south coast, between Fowey and St Mawes, like a giant pair of Ray-Bans.

It is not to everyone’s taste – the couple admit that they would not top a popularity poll of their neighbours – but Blake and Stephens are defiantly proud of their creation. “We wanted to build something that wouldn’t look out of place in Los Angeles or Miami Beach, never mind Sandbanks. We wanted this to be our James Bond fantasy house,” Blake says, looking out across the vast sea view from her living-room windows.

“And I think we have succeeded.”

That Blake, 40, should be involved in such an ambitious project is hardly surprising – she is a flag-bearer for the new Cornish economy that has evolved in recent decades. A local girl, brought up in St Austell, she studied graphic design at University College Falmouth in the late 1980s, and, after a brief spell in London, gained a grant from the Prince’s Trust to set up a graphic-design business. “Just me in a 6ft by 10ft office in Falmouth, with a battered Apple Mac for company,” she recalls.

At first, she worked on packaging, the less than glamorous end of the design business, but it was the 1990s, and people with serious money were coming to Cornwall. They wanted sleek, chic interiors, and Blake saw her chance. She was soon designing for the yachties and second-homers who flew down to the county for the weekend.

Then, in 2005, came her big break, when Jamie Oliver commissioned her to design the interior of Fifteen, his beachside restaurant at Watergate Bay, near Newquay. “I can still remember Jamie’s exact words,” she says. “I had presented my ideas to his advisers and I took his call as I was driving. He just said, ‘Love it, great, go for it.’ It was such a big deal for me.” From that commission sprang work on the £13.5m revamp of the St Moritz hotel, near Wadebridge, north Cornwall, and the Cotton Bay Village resort, on the Caribbean island of St Lucia.

The nous and determination that are Blake’s hallmarks have been poured into Blue Point, where the target buyer has been uppermost in her mind. So, when I put it to her that the entrance to the house from the road looks underwhelming – rather like the delivery bay for a small supermarket – she is quick to defend it.

“It is quite likely that the buyer of this house is going to be a footballer or a film star,” she explains. “Those blank, windowless walls and the security gates are there for a reason: they mean nobody can gawk into the house from the cliffside road. And the reflective windows at the front mean nobody inside can be seen from the beach. So the owner has complete privacy.”

The blandness of the entrance makes the discovery of what lies within all the more surprising. Step a few yards along the main corridor and you find yourself in a glass atrium. Above is a light well, open to the heavens. A limestone staircase with curved glass sides spirals downwards, while ahead are hemispherical plate-glass doors, 13ft high, that open automatically, drawing the eye to windows looking out over an azure-blue sea that blends into the skyline.

“The idea is that when you come into the hall the view is level with your feet, then you walk down the steps so the view unfolds around you,” says Stephens, 39. “Traditional architects like to frame a view, like a picture. We didn’t want that – we wanted a kind of visual explosion.” The living room has the cool look for which Blake is known. On one side is a shiny white kitchen and dining area with a curvaceous white breakfast bar. Elica extractor hoods, flamboyantly disguised as glitter balls, hang overhead. On the other side is the reception. The Lutron lighting has several mood settings, making it easy to spotlight different areas as they are used. It can be controlled from a hand set, as can the Smarthome audio system, which covers every room of the house – and cost £221,000.

While Blue Point is Blake’s baby in terms of interior design, Stephens has supplied the brawn. The couple, both of whom are divorced, have been together for 2½ years. He, too, has been successful in business, although he came up the hard way, leaving school at 16 to start work as a shopfitter. After setting up his own company in 1997, he secured large-scale projects such as fitting out the interiors of the Arndale Centre, in Manchester, and Bristol airport.

Since 2002, Stephens has focused on housebuilding; the Bentley in the drive indicates that he has done well. “It was fitting out those big sites early on that gave me the knowledge to build this house,” he says. “Everything here is on a huge scale. Blue Point measures 12,000 sq ft, and we had to remove 5,500 tons of solid rock before we even started building. Sixty-nine lorry loads of concrete went into the foundations. The logistics of a project of this size are pretty formidable.”

As well as the main living space, the ground floor houses a home cinema with a 9ft by 6ft screen. Opposite is the master bedroom. “I wanted to add just a touch of bling to every room,” Blake says, pointing to the end of the bed, from which a television springs up at the touch of a button. “This is where I can enjoy a girlie movie with a glass of wine when Paul is away. The sun will wake me at about five every morning and I can see the fishermen setting off from the harbour.”

Alternatively, she can delay the day and relax in the £20,000 Teuco bath-cum-whirlpool-cum-hot tub, sunk into the floor of the bedroom and lit by coloured lights.

Down a further flight of stairs are four guest bedrooms and the swimming pool. Stephens recites its measurements as if remembering every ton of rock he moved to build it – it is 36ft by 26ft and holds 15,000 gallons of water. If swimming proves too strenuous, there is also a spa and steam room.

The couple say that they do not expect to make an enormous profit from the project. The original house, a pleasant, box-like detached property of the kind you find dotted everywhere around the cliffs of Cornwall, cost them £1.1m. According to Stephens, demolishing that and building Blue Point cost £2.6m – leaving a dangerously small margin for profit at a time when buyers for such houses are fairly thin on the ground.

So why take the risk? “We know that we’d have made far more money by, say, building eight holiday apartments, which we could have done here quite easily,” Blake admits. “But we really wanted to create this little bit of LA in south Cornwall. It’s a mixture of art deco and 1960s retro, and we are really proud of it. I guess we did it just to prove to people that we could.”

Blue Point is for sale for £3. 875m with Lillicrap Chilcott; 01872 273473, www.lillicrapchilcott.com

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