Don't forget to take ALL docs for the car, originals not copies. Ideal credit card would be MasterCard as some unmanned gas stations, which are getting far more common, don't take UK Visa and most don't take UK Debit Cards. If you intend to exceed the speed limit, make sure you have CASH to pay the fine if you get caught. Minimum fine is 90euro's Max 750euro's. Exceed the limit by more than double you will lose your car (in France)
Have you checked the ring is open when you intend to go? It is only open early evening all next week, closed next Saturday, open all day next Sunday.
As for SatNav, mine is upto date so does not pick up French ones. Don't forget your breathalizers for in France!!


ENJOY,