The best bet for Britons renting cars abroad is to head for Florida, according to a Post Office Travel Money survey.
America's sunshine state offered easily the best value for those wanting to hire a car for a week, with Bulgaria the next cheapest destination, followed by Malta.
But Post Office Travel Money warned that holidaymakers who fail to take out excess waiver insurance (EWI) when hiring a vehicle face sky-high charges if they have an accident.
It said costs in Florida were kept down as the state did not charge for EWI. The survey showed that looking at a seven-day hire, including extras, an additional driver plus 40 litres of petrol, the cost in Florida was just £164.69, with Bulgaria £242.09 and Malta £255.49.
Of the other 10 destinations surveyed, Cyprus was the costliest - at £362.29.
The survey also showed how much drivers would have to pay in 20 countries in the event of an accident or theft if EWI had not been paid.
While there was no charge in Florida, the next-cheapest charges were in Turkey (£400), Bulgaria (£404) and Austria (£471).
The most-expensive charges were in Ireland (£1,186), Switzerland (£1,064) and Portugal (£961).
Andrew Brown of Post Office Travel Money said: "Car hire costs can go through the roof when extras are added so it is understandable that many motorists go for the cheapest rate offered when booking online.
"It can also be very difficult to find out the cost of EWI before travel and it is only when collecting the car that what seemed a cheap deal becomes a very expensive one.
"However, the consequence of not paying for the extra insurance could be a much higher bill if you have an accident or if another driver hits your car and leaves without giving his details."
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If you are a victim of a strike, or any other event beyond the airline's control (including ash clouds!), they must offer you a refund (in which case it's up to you to find a way home) or an alternative flight. While you are waiting for the flight you have the right to food and refreshment and accommodation.
If you are on a package holiday, your tour operator is entirely responsible for looking after you until you get back to the UK.
This is more likely to happen due to the financial crisis, but in some situations you are covered.
If you pay by credit card and it's over £100, you'll get a refund from the card company.
Your travel insurance may well cover you too, but check before you go.
Talk to the airline, and if it is temporarily misplaced they should arrange for it to be sent to your accommodation, and you should be either given cash to cover the essentials in the interim.
If it's completely lost you must wait 21 days and then make a claim for compensation. If you are travelling as part of a package you can claim costs from your operator.
If you are travelling within the EU you need an EHIC card, which gives you access to public healthcare. However, this won't necessarily be free, and if you need extra services such as accommodation for a carer, a helicopter home or a delayed flight, you could end up seriously out of pocket.
The only protection that will guarantee you will be looked after without running up a horrendous debt is by having travel insurance - which often covers up to £10 million of costs.
The most common form of theft is pick-pocketing, followed by theft from a car and bag snatching. Meanwhile, 752,000 of those surveyed had items stolen from their hotel room or villa.
If you have anything stolen, your only protection is insurance. You need to tell the local police immediately and get a crime reference for your travel insurer.