As much as you can fit in your wheelbarrow...
JF
Hee, Hee, Hee, ......or, the equivalent of 10 Thousand Euro, get caught with any more at a British airport, and they can confiscate ALL of it, until you can prove that you are not money laundering, and that it came from a legal transaction,.... in which case , the Euro equivalent amount will be returned, and if Customs and Excise are in a good mood that day, you MAY get back the surplus ,..... MAYBE !!