Luxury Real Estate: With many high-priced luxury real estate remaining on the market for what must seem like ions to sellers, out of the fog London ... and the dust in the air due to the property not yet being fully completed emerges the biggest transaction in the world relative to current listings and sales price. Luxist reported that the two-story penthouse unit of London's nearly completed One Hyde Park was sold for $220 million. This December is the anticipated opening of the mixed-use luxury development.

One Hyde Park is a four-tower complex of 86 condominium mansions overlooking Hyde Park and the Serpentine lake with units that start at around $32 million. Residents receive 24-hour concierge service from the neighboring Mandarin Oriental hotel. The vertical community for the very affluent includes a McLaren dealership in its mix of complementing retailers on the premises.

The buyer has not been identified. However, The Daily Telegraph reported that the identity of the buyer is being closely guarded, swirling rumors circulating point toward oil sheiks and oligarchs. The Holmby Hills, Cal., mansion owned by Aaron Spelling's widow, Candy Spelling, at $150 million, is now number two and remains on the market.

Sources: Luxist, The Daily Telegraph