There is the CC's Rookesbury Park site. I think it is also open to non members? It is certainly geared up for the ferry traffic.
Travelling a little further but on route you will be taking if going home is the CC's Mornhill at Winchester, just off the M3; it certainly takes non members and a phone call will determine how they cope with evening arrivals.
The C&CC's Chichester site is quite near at Nutbourne; even from there you could route homeward up the A3M to the A3 > M25
Just after you come off the Ferry at Caen there is a garage they don't take Credit Cards but do take Debit Cards. I use it on the way back every time we go that way.
Les
------------- The worst day fishing is better than the best day working
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