California real-estate agent Aaron Kirman has sold over $4.5 billion worth of property.<br />According to Business Insider, Kirman says the ultra-wealthy don't buy real estate like most middle-class buyers do.<br />They use so-called 'whisper listing' to sell their homes, without making them available to the public.<br />A whisper listing allows the wealthy to list their homes above an area's median listing price.<br />Another reason is privacy. <br />
