Posting things abroad - what do I say? How do I add this option to a listing?

[AnarchyAunt]

I'm selling some clothes (only just started selling so am hopeless at it) and have had two enquiries on the cost of posting to elsewhere in Europe. On the listing I only gave the cost of domestic postage and can't now work out how to add cost for European postage - is it possible?

And if not, what do I say? I'm happy to post the item to Europe so can I just ask them to pay the extra once I've worked out how much it will be, even though it's not what the P&P are listed as?

[AnarchyAunt]

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