Forget about a fool and his money, recent figures from the Air Transport Users Council (AUC) show passengers and their luggage are parted to the tune of 30m lost bags a year.

With Heathrow at breaking point and other airports not doing much better, plus bad weather, increased security and creaky old luggage systems, it’s hardly surprising that one insurance company this week reported an 85% increase in claims for lost bags in just 12 months.

The AUC points out that 85 per cent of bags are reunited with their owners within 48 hours. But what happens to the remaining 15 per cent? If, after three months, the airline hasn’t traced the owner, they come to auction houses such as Greasby’s, in Tooting, south London.

About 1,000 unclaimed items pour into Greasby’s each month. Shoes, electricals, valuables and accessories are removed from the cases and sold separately; the cases themselves are sold sealed, containing only the clothes.

I’m here on a mission: hoping to find a suitcase of hen-party accoutrements lost somewhere between Heathrow and Berlin back in June. It’s obviously a long shot that I’d get the right week, but I’ve tried everything else and this is my last chance.

There’s another hen do in September, and I don’t want to make any more bubble-wrap bikinis unless I absolutely have to. Besides, one lucky couple did turn up about three years ago to find their bag.

Queuing to pay my £100 refundable deposit in exchange for a catalogue and bidding card, I meet Sue. “There are so many professional dealers on eBay these days,” she says wistfully. “I thought I might get a better deal on a used laptop here.” (Since 120 laptops a month are handed in at Heathrow alone, she could well be right.)

Downstairs, the auction hall looks like a cross between a village hall and a lockup: it’s a curate’s egg of unclaimed Samsonite cases, oil paintings, surfboards and blood-pressure machines. In glass cabinets, the latest mobile phones and MP3 players sit next to plastic bags bulging with cosmetics and neatly brushed toupees.

A library of high-altitude literature stretches from floor to ceiling, and from the rafters hang colourful bunches of sandals and flip-flops, like artificial bougainvillea.

Scattered around the hall, 60 potential buyers carefully inspect the piles of wetsuits, guitars and pushchairs, and a six-man canoe, diligently cross-checking the number on each item against its description in the catalogue.

The back wall is piled high with luggage, though, sadly, there’s no sign of my pink Kipling case in the great wall of Antler. Ken and Lesley are also inspecting the cases: they got bitten by the auction bug two years ago and treat it as a hobby. “Waiting for your lot to come up, bidding... it’s really exciting,” grins Ken. “It can be hit and miss, though,” cautions Lesley.

“You’re paying between £8 and £10 for a case, and they’re sealed, so you never know what you’re going to get.” How do they decide which to bid on? “You look the cases over carefully,” Lesley says. “Then you go on instinct. We’ve had some nice designer clothes. Just last week, I got an Amanda Wakeley dress.” “It’s like Christmas,” Ken says gleefully. “Opening the cases... it’s like opening presents.”

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