Wish you'd kept that Biba dress or Hermes bag from way back when? You probably should have.

An increasing number of savvy, wealthy, shoppers are attending vintage fashion auctions to snag designer clothes and accessories by the biggest names in the industry. According to Christie's auction house, while the majority of lots in its fashion sales are still bought by dealers or collectors, around 15 per cent of buyers are ready-to-wear customers who fully intend to wear the design classics they bid for.

As part of its 20th Century Fashion sale in London this week, Christie's auctioned off original Ossie Clark - the fashion label relaunched during February's fashion week - couture Chanel, and a host of Hermes and Louis Vuitton bags and trunks.

Junior specialist Monica Turcich advises against buying fashion solely as an investment, but says fashion lovers should get something they like with an eye toward selecting pieces that will increase in value. What's certain is you're guaranteed to get something unique, if not a little delicate (as Kate Moss's vintage Dior dress illustrated when it ripped last year).

The reserve prices for some of the outfits were as low as £400 for a Pierre Balmain Couture dress and jacket, but the prices go much higher. One forest green crocodile Kelly Hermes bag, estimated to sell for £15,000, fetched almost double that.

Fashion writer Alice Olins previewed some vintage lots and talked to junior specialist Monica Turcich about the clothes, her clients' Antiques Roadshow moments and explained exactly how to tell whether a Hermes bag is a fake.

Click above to watch the video.

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