A sudden drop in income, a mounting medical debt and a family to feed left Sheraz (not his real name) struggling to find another way of making money.

During the pandemic his wife lost her job as a beautician, and the government's pandemic support was not easily available to him.

So, he turned to "scalping" - an unfavourable term for stockpiling popular products and reselling them at a higher price for profit.

Many sought-after items are resold, including concert tickets, limited-edition trainers and games consoles.

While the general resale of football tickets is illegal, practically everything else is legal to buy up and resell.

Sheraz says he only sells to his friends and family to make about £250 extra a month, so that he can "slowly eat away" at a £50,000 medical bill.

But for a majority of resellers, scalping is big business - and they are using tech to give them an added advantage.

Online bots

A lot of electronics are in short supply because of a global shortage of semiconductor chips, which are essentially the brains of modern electronic products.

Cars, graphics cards, smartphones and games consoles have all been affected.

The PlayStation 5 - Sony's next-generation games console - has been particularly hard for many gamers to get hold of.

Some shoppers relied on leaked information from big retailers to predict when new stock might become available. But even those staying up until 03:00 excitedly refreshing a retailer's website would find the stock sold out in minutes.

Real shoppers were being beaten by bots.

Software developed by the scalpers can notify them as soon as stock is available from any of their target websites. Sometimes the bots can even automatically buy items.

The PS5 consoles were being snapped up by bots, only to be resold for twice the regular retail price of £450.

Meeting the scalpers

Jack Bayliss is a 24-year-old former investment banker who started reselling six years ago. His profit margins were huge - sometimes he would buy Yeezy trainers for £150 and sell them for up to £1,000.