Need to Know: The mission - What exactly do millionaires have in their houses?

Nicholas Barber snoops, with the aid of a Kensington estate agent

sk a west London estate agent what

he's got for sale around the pounds 2m mark,

and, just as long as you can get out those last few words without choking, you'll be amazed by how quickly he'll fix you a viewing appointment. I was slightly afraid that I'd have to produce a year's bank statements before I'd be allowed to peek through the keyhole of a stranger's pounds 1.8m pied a terre, just down the road from the Albert Hall. But, no, the estate agent was happy to imagine I was an eccentric aristocrat slumming it in jeans and a sweatshirt. "How many people are going to be living here?" he asks as we roam through one of the drawing rooms. "I don't know," I mumble. "Two, maybe?" "Let's have a look upstairs," he chirps. He doesn't seem surprised to hear that two people might find a use for six bedrooms and five bathrooms. Perhaps he assumes that I'm a diarrhoea-prone hide- and-seek addict, but, to be fair, why should he be suspicious? I doubt he often has to deal with someone who has no intention of buying a property from him, if only because most of us don't spend any more time in the company of estate agents than is absolutely necessary.

Both this house and one I nose around in Mayfair have been newly renovated and decorated, so I can confirm that minimalist, loft-style decor with a hint of MFI is de rigueur for the discerning Ferrero Rocher-eater. The other salient features of luxury living are endless storage space (one advantage of having five storeys: lots of cupboards under the stairs, sausage-shaped neck-cushions which rest at either end of the bath and little spotlights embedded in the ceilings - "low-volted downlighters", to be exact. Best of all, these lights go on gradually. Hit the switch, and there's a slight pause before the bulbs ease themselves gently to full power. Not for millionaires, that harsh sudden brightness which so taints the lives of the poor.

Next, I visit a cosy mansion which is a snip at pounds 1.6m. (It is, says the advertisement in a Sunday newspaper, "charming".) The couple who own it feel that two homes are enough for them these days. "Barbados and Jersey is a nice mix," explains my host. "Barbados, Jersey and London, though, you never have enough time to enjoy them all." To the untrained eye, this particular residence could be your average middle-class household, only three times bigger and a short stroll from Kensington Palace. You don't have to be Loyd Grossman, however, to spot a few clues to the owner's bank balance: the Oriental maid and the 19th-century paintings, for instance, and the fact that the larger rooms have two phones each. (At last, an end to those how-come-the-phone-always-rings-when-you're-at-the-other- side-of-the-room frustrations.) And, of course, location is everything. As we're leaving, the estate agent reveals another selling point: "The Tube is just 100 yards away." I'm sure the lucky purchasers, whoever they might be, won't travel any other way