Denzel Washington spent a measly $12 million on his apartment at 15 Central Park West, while Sting coughed up $26.5 million for a unit in the same building. But both pale in comparison to the $88 million that Ekaterina Rybolovlev—daughter of Russian billionaire Dmitry Rybolovlev—dropped in 2011 for a spot in the high-end residence.