i worked in lived and Worked in Calais
Worked in a Beer Yard

Dont need to take Euros as all the British Beer yards take Sterling
Oh and there's no limit on French Duty paid, so fill ya boot and your back seat
I used to get 30 cases in my old s2
Just make sure you get a Reciept for any goods as its your proof that you paid french duty as Customs will ask for it if you get a tug
Oh, and if you are on the boat, theres no real time scale so you can catch any boat you like so no need to rush if you think you are going to mis one. Even thou your ticket will show a ferry time , just ignor that you can get on the first available thats in dock and there's another Ferry every 45 mins