Sometimes people ask us what the most expensive, surprise item has been for us living in Europe. During our Italian sojourn I would say it was the combination of incessant highway tolls and parking and moving violations, the latter of which we accumulated many--out of ignorance mostly, as we were not careful enough to mimic the locals' patterns of speeding up and slowing down. Which appeared random at first, as we mistakenly assumed they were the result of the Italian laissez-faire attitude of driving. But come to find out they were closely attuned to the position of speed cameras. Parking fees were mostly of our own making (by 'our own' I mean 'Stewart's'), and our oblivious jaunts into forbidden ZTLs, the inner city zones that require special permits, were not cheap either.
In Dublin, it is turning out to be the gas and electric bill. While San Diego takes the cake in that category, Dublin is seems is not far behind. The matter isn't helped by our quixotic heating system in the apartment that randomly creates a steam-room setting in the hallway and one of a refrigerator in the kitchen. An honorable mention goes to the Irish TV tax: a two hundred dollar ANNUAL fee for the privilege of having a television in one's home.
Putting those things in perspective though, we have been lucky. It could have been most certainly worse, and for that we consider ourselves fortunate.