Mark Cuban, the billionaire entrepreneur and investor who started with just $60 in his pocket and had to move into a friend's apartment after college, has amassed a fortune of more than $5 billion.

Cuban's entrepreneurial spirit began at a young age, with ventures like selling garbage bags at age 12, transitioning to selling stamps and coins and even running a small newspaper business during a strike in Pittsburgh at age 16. His determination led him to pursue a management degree in college, setting the stage for his future endeavors.

Cuban graduated from Indiana University in 1981 and began working at Mellon Bank in Pittsburgh. At Mellon Bank, he transitioned paper-based processes to computer systems. He also initiated a newsletter and organized a happy hour group for younger employees to interact with senior executives. His boss wasn't supportive of these efforts.

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"He told me I was never to go over him or around him, or he'd crush me," Cuban recalled in a Forbes essay. "I knew then it was time to get out of there."

After leaving Mellon Bank, Cuban worked at the TV repair franchise Tronics 2000 in Indiana before moving to Dallas. When he was 24, Cuban shared a three-bedroom apartment in Dallas with five roommates. He had just $60 to his name.

Cuban attempted to start his own business selling powdered milk but quickly realized it was not a viable venture. "I honestly thought it would make a killer business and it lasted minutes," Cuban said.

Next, he secured a position at PC software company Your Business Software, earning $18,000 per year plus commissions. This role was also short-lived. Cuban had an opportunity to make a $15,000 sale, which would have yielded a $1,500 commission. It was a chance for him to improve his living situation.

He informed his boss — the company's CEO — that he intended to close the deal during his regular shift, with someone covering for him. His boss, against his plan, forbade him from going ahead with it. Cuban proceeded anyway, thinking that his boss would be impressed with the sale.

Instead, upon returning to the office, his boss promptly terminated him for disobedience. Cuban described this incident as "the determining factor in my business life."

This setback motivated him to establish a PC consulting company named MicroSolutions, which he later sold to CompuServe for $6 million. 

Building on this success, he founded Broadcast.com, an internet radio company. Yahoo! Inc. acquired the company in 1999 for $5.7 billion in stock. Despite the potential for his wealth to increase further with Yahoo's rising stock prices, Cuban decided to sell his shares immediately. This choice turned out to be a smart move — the dot.com bubble burst shortly after, marking Yahoo's acquisition of Broadcast.com as one of the most ill-fated deals in history. Ultimately, investing in himself and investing in the world of startups, paid off for Cuban.

In 2000, Cuban purchased the Dallas Mavericks NBA team for $285 million. Now Cuban is worth $5.1 billion, according to Forbes.

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