Yeah, do a turbo-diesel. Expand your mind - try a French car
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If you have to pay to park in the cities, it gets pretty pricey but I could never do it by train - having the car to keep stuff in, and the flexibility, is awesome.
However, John's got it right - if you are ONLY in cities, use the train. Parking and Euro city driving will kill you (remember, many of the cities are much older than cars and not designed for it).