Cameron Diaz, who dated Justin Timberlake after Britney Spears did, is considering following the troubled singer’s lead on Manhattan real estate, too. She was recently spotted at an open house in Noho’s Silk Building—where Spears once owned a quadruplex that took her years and countless price cuts to sell. Diaz showed up sans broker to look at a $1.699 million two-bedroom, listed with Prudential Douglas Elliman’s Lisa Maysonet. (Russell Simmons, Keith Richards, and Cher have lived in the building; Tower Records was downstairs.) Diaz was last seen apartment hunting in West Chelsea. She’s returned numerous times to a West 19th Street building, says another tipster, but for a plusher, more expensive—$5.5 million—four-bedroom penthouse. The unit’s listing broker, Frederik Eklund of Core Group Marketing, wouldn’t comment.