Portofino is definatelly very charming place and probably one of the most attractive day trips I had during visiting of Liguria. It is, however, ridiculously expensive place. I am not a miser but cannot accept the fact that one single espresso could cost six or seven times more then in the rest of Italy. But its not the espresso only, everything here looks very overpriced.
Unique Suggestions: If checking cash money, on departure from Portofino, one might have impression that were sacked. I was in two cafe-bars, having espresso and water in one and only espresso in another one, and since we were in two it have cost me 50 euros.
Fun Alternatives: Take a walks explore the place and do alot of photos if having a camera, if you sit in a cafe it will cost you dearly!