“The sizes that get a higher resale value are usually the smaller ones – for Birkins, 25cm is preferred, then 30cm. Kelly bag resale values are highest for the 25cm and 28cm sizes,” says fashion blogger Ingrid Chua.

The construction method also plays a part: “Kelly structures come in sellier mou (which are outside stitched, hence more rigid in structure) or retourne (inside stitched, so the structure is softer). Sellier mou is the more expensive way to construct a Kelly, and is considered rarer. Birkins used to come only in retourne, but the sellier mou has since become an alternative that’s not as regularly offered,” says Chua.

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Among more “regular” models, certain leathers are more desirable – Himalayan croc skin is definitely the pinnacle, but collectors also appreciate barenia or box calfskin, often used in vintage models, and chèvre. Regular leather Birkin and Kelly bags that are considered more “unicorn” are “purple-hued ones like anemone, lilac and pastel pink shades like sakura. VVIPs are given the privilege of special orders, and having a bag combination with those shades will really make your friends green with envy,” Chua adds.

For those who are looking for the extraordinary, there are the unique finds that show up on auction blocks – with price tags to match. Winsy Tsang, head of sales at Christie’s, concurs that Himalayan Birkins and smaller-sized models tend to fetch higher returns, including miniature bags such as the Kelly Pochette, Mini Kelly and Mini Lindy.

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She also notes, “oversized bags have also returned as a new must-have item, with its refreshing practicality making waves in the fashion world. We are also seeing more male collectors participating in Christie’s handbag auctions, bidding for the larger 40- to 50-inch men’s bags”.

The Himalayan Birkin may be the model that breaks auction records, but models from the So Black collection, featuring black Niloticus crocodile skin with black hardware, were discontinued in 2010, increasing in value over time.

“Hermès limited editions are incredibly difficult to obtain in the market, [and are] a great choice for collectors as the desirability for these special editions skyrocket once released,” says Tsang. Examples include the “playful” Quelle Idole, aka the Kelly Doll, which has been discontinued, and is even unavailable for custom-made orders. Emblazoned with a grinning face and dangling arms affixed to the side of the bag, this is certainly an attention-grabbing investment.

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A custom matte bleu paon alligator and rose pourpre swift leather Quelle Idole, with gold hardware, will be going on the block at a Christie’s with a presale estimate of HK$350,000-HK$400,000 (US$45,000-US$52,000) – exceeding the estimate for a 30cm So Black Birkin, which is still a hefty HK$300,000-HK$350,000.

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