Travel is expensive enough at the moment without adding to the costs with bad financial decisions over your holiday money. Yet we fall into the same old traps year after year. We take out too much cash and pay over the top for it. We use the wrong credit and debit cards and we get our sums wrong when we try to work out how much things really cost. Sometimes we even fail to claim substantial refunds to which we are entitled. To help you avoid the pitfalls, we have put together a guide to the most important mistakes to avoid. Even if the amounts saved might seem relatively small for each purchase, over a couple of weeks’ holiday they can quickly mount up. You will nearly always pay a premium on the exchange rate at an airport bureau de change – unless you order online in advance. And in any case, in many countries you simply don’t need cash on arrival any more. I no longer travel with any paper money. It’s true that, in some countries, cash still dominates – for example, in Malta, 88 per cent of payments are still made in cash, and in Spain and...