ITALY: Not having cash with you
When in Rome, keep the plastic in your wallet. It’s not that you won’t be able to pay by credit card at shops or restaurants but it’s better to carry some cash with you, just in case. And it’s not just any cash you should have in your wallet, it’s the smaller bills that are extremely important.
Why? Because some shops will not be able to give you any change to your large bill. You don’t want to come back from a shopping spree empty-handed, do you?