When Cuban was 12 years old, he asked his father for a new pair of sneakers. His father just watched his shows, said they seemed fine, and that if we wanted new ones he’d have to go get a job and buy them himself.
Cuban, being 12, had no idea how to do that. But one of his father’s friend had an idea. The guy had some garbage bags he needed to offload, and he suggested Cuban go door-to-door and sell them for a profit.
According to Business Insider, which transcribed Cuban speaking on a Bloomberg podcast: “They were 100 for six bucks, what I sold them for — they cost me three bucks, so I made three bucks a box. And I would literally go door to door to door: ‘Hi, does your family use garbage bags? And who could say no? So that's where I learned to sell. Literally. Every objection [I'd reply], ‘Of course you use garbage bags, and I bet you pay more than six cents a piece.’”
It was his earliest foray into money making schemes, which was something he’d pursue into his young adult years.
One more scheme from Cuban’s childhood: he would buy baseball cards, repackage and sell them from a park bench in Pittsburgh. His sales pitch: each pack would be guaranteed to have a Pittsburgh Pirate.