World’s Mega-Rich Bet on US Renters to Grow Their Billions

Chicago’s 727 West Madison tower — a luxury residential building with poolside cabanas and a yoga studio — sports a new owner these days: the billionaire founder of the Zara clothing chain.

Amancio Ortega snapped up the building in Chicago’s West Loop neighborhood last month for $232 million, joining a growing number of the super-wealthy betting on US renters.

Amancio Ortega

Photographer: Iago Lopez/AP Photo

Over the past decade, ultra-wealthy individuals and their firms have more than doubled their investments in apartments, largely in the sector known in the US as multifamily housing, according to research from Knight Frank.

Today, many of those investors are ...