The self-made billionaire was born to working-class Polish immigrants and grew up in a modest one-bedroom apartment. : After a successful 25-year career at Goldman Sachs, billionaire investor Leon Cooperman left to start his own hedge fund, Omega Advisors, in 1991. Today, his firm manages approximately $3.4 billion in assets. But the Wall Street legend wasn't born rich: His parents were working-class Polish immigrants and he grew up in a one-bedroom apartment in the South Bronx.