Although I have long since ceased to worry over the cost of petrol ( ownership of a Jaguar Series III convertible back in the '70s and many other multicylindered cars since then - never ever less than six pots ) anaethesised me against worrying about gasoline prices. However, getting a price for a ferry crossing with a car from Portsmouth to Santander really blew my socks into the long grass. It is £800 quid even for an inside cabin. So bugger that, I'm going back to the Cote d'Azure or even Tuscany.
I'd still like to tour Portugal, but maybe I'd rent some wheels over there .
As for what car I'd take, it depends if my 18 year old daughter wants to come. If she does ( and hopefully not ! ) I'd take my Bentley Continental GTC. If not, then we'd rough it using the wife's DB9 Volante............and against the GTC that really is roughing it.