Live like world's second richest man! Mexican billionaire Carlos Slim is selling historic Fifth Avenue mansion for record-breaking $80million
- Slim, 75, bought Benjamin N. and Sarah Duke House at 1009 Fifth Avenue for $44million in 2010
- Beaux-Arts home built in 1901 overlooking from Central Park has eight floors and measures 20,000 square feet
- Duke House is one of last private mansions along portion of Fifth Avenue once known as Millionaires' Row
- Slim, whose net worth is $77.1billion, has lived for past . . .
