Pre-Owned Dream Girl (Hardcover) by Lauren Mechling

CLAIRE VOYANTE HAS been having strange visions ever since she can remember. But the similarity between her name and her talents is purely coincidental. The name is French, and unlike the psychics on TV, she can't solve crimes or talk to the dead. Whenever Claire follows her hunches, she comes up empty--or ends up in pretty awkward situations.
But that all changes on Claire's 15th birthday, when her grandmother, Kiki--former socialite, fashion icon, and permanent fixture at the Waldorf Astoria Hotel--gives her something a little more extraordinary than one of her old cocktail dresses: a strange black-and-white onyx cameo on a gold chain. It's not long before Claire's world becomes a whole lot clearer. And a whole lot more dangerous.