Where to cross
A cheap fare can cost you a day's driving.
Dover to Calais is the cheapest and most frequent way across, and the easiest with a tall van. It also lands you the best part of a day's driving from the west of France.
The Western Channel boats cost more and sail less often, but Normandy and Brittany start at the ramp. Add the French tolls to the Calais fare before you compare the two.