Exploration and discovery are yours for the taking when you hire a car on holiday. But without a little planning, you can end up paying way over the odds.

Protect yourself by getting to grips with the seven worst car hire rip-offs.

Rip-off #1: Sky-high excess costs

When you hire a car, insurance is included. But you may well find it comes with incredibly high excess charges – the amount you have to pay to cover the cost of an accident before the policy kicks in. This amount can be up to £2,000, in some cases – potentially leaving you well out of pocket if something goes wrong.

One way to get around the charge is to buy an excess waiver policy, which reduces the charge to zero or a small sum. But don’t wait until you get to the desk! Buy your waiver at home before you travel and you could pay around a mere £3 a day, compared with up to £20 if you don’t plan ahead.

Rip-off #2: The ‘full-empty’ fuel policy

Being hit with a petrol bill before you’ve even got in the driving seat isn’t the best start to a holiday. But many car hire companies employ a so-called “full-empty policy”, which means you pay upfront for a tank of petrol and can return it empty.

But there are two drawbacks to such a policy. First, you’re likely to be charged an inflated price for the petrol. And, second, you may not use all the fuel you’ve paid for if you’re on a short trip or don’t end up driving much.

In some cases, you’ll be offered the right to a refund on unused fuel, but there’s still usually a service charge attached.

Look for car hire firms that allow you simply to return the vehicle with the same amount of fuel it had when you picked it up.

Rip-off #3: The ‘upgrade’ option

When you arrive at the rental desk to pick up your pre-booked car, you may be told the company has run out of vehicles in the category you chose and be offered an upgrade – at a price.

Don’t fall for it. You should either be offered a higher-category car for no extra charge or a lesser one with the appropriate refund.

Make sure this is the case before you sign your contract and drive away.

Rip-off #4: Paying for extras you could bring yourself

Want to use sat-nav when driving abroad or think you’ll need a baby seat? Fine – but don’t fall into the trap of hiring them through your car rental company. It’ll be cheaper to bring your own.

If you’re travelling abroad, charter airlines don’t charge extra for you to bring pushchairs and car seats, while many sat-navs cover both the UK and Europe. If your sat-nav doesn’t extend beyond the UK, consider purchasing the additional software or download an app on your smartphone.

If all else fails – there’s always the option of a good old-fashioned map.

Rip-off #5: Buying at the desk

With so much to organise before a holiday, it’s easy to put off hiring a car until you arrive at your destination. But booking a vehicle in advance – and online – will save you a chunk of cash, leaving you more to spend on the good stuff.

What’s more, if you book at the destination airport, or other pick-up point such as in a city centre, you risk ending up with an unsuitable vehicle – when demand soars in peak season, for example.

Rip-off #6:  Unexpected charges when you get home

You expect to return from holiday with a lighter wallet – but it’s infuriating to find extra taken off your credit card for a bill you thought you’d squared.

The main reasons for car hire firms to charge more than you expected is when they claim you’ve damaged the vehicle in some way or that you returned it without the agreed amount of fuel.

To protect yourself, give the vehicle a full inspection both when you pick it up and when you return it and ask for a receipt stating it’s in good order with the required amount of petrol.

Rip-off #7: Hidden charges

Always read the small print of your car hire policy to check for any hidden charges or exclusions.

Some car hire companies, for example, charge extra if you’ve been driving for less than four years, while others charge more for including a second driver.

And others will levy an “admin” fee for theft or damage to the car – even if you’ve bought an excess waiver policy.

To put it in a nutshell: being thorough in your research when hiring a car is the way to get the best deal.

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