Welcome to the site Chris - Hope all is well in London :)
After looking through various Pandora beads listings on eBay there doesn't seem to be a recognized norm at how you should market them.
Most sellers list individual Pandora bead and may offer additional discount if a buyer buys 4 (for example) of the same design. While other sellers offers combined shipping discounts if you buy 3-2 beads or 4-10 beads.
One seller was selling them at sets of 6, 2 beads per set. Like this listing -
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(Please note I don't the seller and I'm just showing an example)
You can vary your listing to have both Buy It Now items as well as auction type listings. You can also very the duration of your listings and the start time. And see which one works best for you.
Hope this helps.
Do add a photo the next time you're in - thanks!