I've just purchased a small camera accessory from eBay.
The same item was available from about a dozen different companies.
Most of the sellers are UK based, and they're all charging £3.40, with free shipping.
Two of the sellers are from Hong Kong, one is charging £2.59, and the other is charging £1.59, both are offering free shipping.
The item weighs about 50g, and will probably fit in a small jiffy bag. If I send something that size to Hong Kong it would cost £3.30, but even if it only costs them £1 for shipping I can't imagine how they make any money considering the Ebay & Pay Pal fees
It might surprise you how cheaply something like this can be made for. If £100 trainers can be made for £5-£10 and £60 casual shirts for less than £5 it gives you some idea of the sort of mark-ups that are made. If you dig a little you might also be able to find some ideas about how little an iPhone or Ipad is made for when compared to its selling price.
I also dont think you realise just how cheap international shipping is these days. It probably cost more to collect the container it was in from the docks and drive it to a depot than it cost to ship it halfway round the world.
Has I mentioned earlier, I have purchased many various items from these sources, and all arrive with the necessary custom's declaration, which places the item below the UK tax limits. Never yet been asked for extra payment, but I suppose there is always the first time?.
I have even purchased a number of the same items, and all have arrived individually packed, instead of one larger package. Usually arrive together or within a day or two of each package.
Perhaps worth a mention, that the delivery time can take anything from 7 days to over 21 days, even though the seller usually ships fairly fast. Usually 1/2 days after payment received.