Decor is so key, says Sami Robertson of Knight Frank, that some City clients won’t even look at a prospective flat unless it is bright and modern.

Whether you have just bought a home and want to revamp it, want to sell your existing one and get the most for it, or are letting in a saturated market, calling in an interior designer can pay dividends, and isn’t just for the well-heeled.

If you have cash to spare, every little detail will be addressed.

“Twenty years ago, we would rarely get clients asking us to provide towels and sheets,” says London designer Joanna Wood, whose renovations range from £25,000 to £25m. “Today, about half of our clients want us to do the whole thing.

“Yesterday, I was sourcing a special kind of duster and drying cloth for a Russian client. For another, I had to make a ‘shaking watch’ drawer that will automatically wind up his collection of Rolex watches!”

Helen Green’s refurbishments in London’s Belgravia, Chelsea and Knightsbridge cost from £75-£120 per square foot, for ultimate luxury (so about £120,000 for a large two-bed flat, with everything installed). She says quality is imperative at the high end of the market.

If you have more dash than cash, you can get top-notch advice. Alison Henry, whose projects mostly cost more than £1m, will consult (for £350 an hour) on paint finishes, furniture, art and details, and clients can project-manage themselves. “Some people just need guidance as to how to improve what they’ve got,” she says.

“If you are overhauling the decor because you are trying to sell, stay focused,” says Hamptons director Ian Westerling. “So even at the high end it’s worth finding a decorator whose decor and furnishings will be chic yet neutral, without looking bland.”

Where to find a designer?

Martin Waller, the man behind the annual Andrew Martin Interior Design Review, suggests browsing that, or looking at the British Interior Design Association website: “It’s important to find not only someone whose taste you admire — and will work for whatever vision you have — but someone who you will like. If you’re spending a lot of money and a lot of time with a decorator, and they’re choosing everything for you, you want to enjoy it.”

For those on more modest budgets, John Lewis, Habitat, Oka, Multiyork, Laura Ashley and Lombok all offer design services and, unlike professional designers, they charge little or nothing; they bank on you buying what you need from them. John Lewis charges £200 (refunded against the cost of furniture) to visit a client’s home, come up with mood boards, furniture suggestions and window-dressing plans, then co-ordinate delivery and installation.

Last year, Helena Fletcher of John Lewis redid an entire London flat for £80,000. This covered design, installing a new kitchen, finding decorators and refurnishing, recurtaining and restocking the home.

“All he had to do was look at the designs we’d come up with, based on the sort of style he wanted, come into the store to fill in paperwork and look at the furniture we recommended.”

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