4Get a receipt
It’s illegal in Italy not to be given a receipt. So you should always get one anyway – but if you’re suspicious about something, make absolutely sure you get it.
And one for the road..
Getting a taxi home? Check the prices. Roman taxi drivers have a bad reputation – the guys at Ciampino airport who insist on quoting astronomical prices for a trip into town, when the fixed price of €30 is written on the door