Wahaaj Shabbir is regarded as part of the first generation of eBay (EBAY) "flippers", the art of buying and reselling for a profit. His expertise also helped to secure his first job at the global online marketplace.

Shabbir is now eBay UK’s head of sneakers, a category which has seen such exponential growth in recent years that a pair, either new or pre-loved, is sold every five seconds.

“When I was growing up it would have been a hard ask to get me wearing a pair of second hand sneakers,” says Shabbir, "but the perception of wearing pre-loved is no longer stigmatised.”

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Shabbir did purchase his first pair of Nike (NKE) Air Max sneakers through eBay. He also queued for two days outside a London store before even having the chance to buy another pair of Nikes. After shelling out ￡120, a week later he sold them for over ￡4,000.

“I was selling anything and everything,” he recalls. “One day I was selling sneakers and the next china plates or tyre pressure monitors. I would buy stuff in winter, like paddling pools, to sell in summer.”

It was, he says, a decent side hustle while studying mechanical engineering at the University of Liverpool. In nine years he accrued over ￡500,000 in sales. His best period came when he sold ￡60,000 worth of Nintendo consoles in a fortnight.

“For someone sitting in student accommodation, it helped to pay my way through university,” he says of his venture.

When he finished his studies, Shabbir closed his business down for mental health reasons and worked in a newsagents on 4am shifts, part-time at Uber Eats (UBER) and Amazon Flex (AMZN) app as a delivery driver while trying to land a job. On LinkedIn, he applied for as many jobs that fit his criteria before he came across an eBay internship role.

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“It felt like a natural fit based on the fact I had an eBay business," he admits. “Even though I had it for nine years, I feel like no one really appreciated what that meant, but it was a real business. When I went to eBay it felt like the first place which appreciated that experience.”

An interviewer had searched for his eBay account and saw that he was a top-rated power seller on the system. “They gave me a break and the stars aligned,” he admits.

Having joined in 2019, he was made head of sneakers in 2022 and oversees a market which has been born out of the US and basketball's popularity. It led to the launch last year of eBay's authenticity guarantee, to cover branded sneakers costing more than ￡100.