Ten thousand square feet of Regency splendour sitting right on Hyde Park - what's not to love? A few things, actually, but the size of this place is immensely appealing, as is the grandeur, location and huge potential.

There are a couple of quibbles, the price being the main one. How much for this near-palatial maisonette (a term that seems inadequate for a sprawling three-storey conglomerate of rooms that spans two house widths)? £18 million. Not a sum often associated with maisonettes, but it does include a mews house with development potential located in the next street, above garaging for three cars, and a large private terrace at the rear of the house.

Which brings us to the second hurdle: the road. Running past the garden back wall, the Bayswater Road separates the house from the north side of Hyde Park, a fact hard to forget when sitting on the terrace listening to the 148 bus trundle from Notting Hill Gate to Marble Arch. Come summer, apparently the foliage will block much of the noise pollution. The terrace is at first-floor level, with access from the main reception suite, and steps lead down to a shared lawn that backs on to the tree-filled borders fencing in the garden.

Inside, the main rooms are stately to say the least, with soaring ceilings and ornate decoration. The predominance of gilt proclaims the status of the present owner, who comes from the Gulf. Unfortunately the servants' quarters reflect their lower status, with an unequal allocation of space beyond even the usual upstairs-downstairs culture; for some rooms there is no better word than “bling”, while referring to others as dingy would be generous.

This built-in imbalance means the place is crying out for an architectural overhaul. The brown-tiled kitchen is disproportionately small. A mezzanine has been fitted to create a dining room, cutting one reception room in half horizontally. This is a shame, as ceiling height is a defining feature of these great, stucco-fronted mansions, and one of the advantages of living on the first and second floors.

There are two types of buyer for this unlikely gem: loaded and Middle Eastern, or loaded and Western. The first could maintain the current style, negotiating the purchase of furnishings and extras (a tropical water feature in the entrance hall; gold sinks in the downstairs loo; the executive stairlift - you can see this running beside the banisters in the photograph of the incredible staircase, below). The second buyer-type could hire an architect and let imagination run wild. The obvious barrier for this person - and there have been a few offers, all refused - is the pricing: £18 million is somewhat hefty as an initial purchase price before dropping a further million or two on the overhaul. In market terms it is overpriced, but in real terms this much space in this location may not come up again for years.

Contact: Quintessentially Estates, 0845 2243658

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