It should be so simple; such a stress-free run-of-the-mill part of a holiday. Yet I hear more complaints from readers about car hire companies than about any other single issue. And that is despite the fact that in 2015 the Competition and Markets Authority (formerly the Office of Fair Trading) carried out a review of car hire in the UK and in Europe and ordered rental companies to clean up their act.

So what is going wrong? Why are readers still having bad experiences, and what more needs to be done to sort the issue?

Spanish car rental firms turned out to be the worst offenders: the CMA and its Spanish equivalent discovered major infringements in 32 of the 100 businesses

First, the background. The CMA investigation, held in tandem with its European counterparts, looked at the online price transparency, terms and conditions and general behaviour of rental companies, including five of the major players – Hertz, Avis-Budget, Europcar, Enterprise and Sixt – which provide two thirds of the rentals in Britain and the EU.

Overall, however, it was Spanish car rental firms that turned out to be the worst offenders: the CMA and its Spanish equivalent discovered major infringements in 32 of the 100 businesses so far checked, and the process is continuing.

Following the publication of the report, in July 2015, car rental companies were given six months to shape up. They were told to provide transparent pricing, give prominent links to a new “key facts” document and to the supplier’s terms and conditions, explain the full extent of liability and waiver cover, and offer a full-to-full fuel option. These latter two points stemmed from high charges for insurance top-ups, and for refuelling cars. Another issue was unaccountable, post-rental charges for accidental damage. The report also said that when damage did occur, customers were to be sent evidence of it and how the repair cost had been calculated, and have the opportunity to challenge it before their credit card was debited.

The biggest bugbear continues to be aggressive sales tactics used by staff at the pick-up desk to sell damage waiver cover Credit: © Daniele Pietrobelli / Alamy Stock Photo/Daniele Pietrobelli / Alamy Stock Photo

Since then, my own research has confirmed a marked improvement in the level of information and price transparency provided by the five major players on their websites. There are still issues with some UK brokers, but the CMA has since been working with them to follow suit. Overall, the UK vehicle rental trade association, the BVRLA, which has 270 members, and its European counterpart, Leaseurope, now have more robust codes of conduct and provide mediation services for customers. But it’s certainly not game over. Some of the old issues are still entrenched and car rental suppliers – or at least the companies that operate the local franchises – continue to think up new revenue earners.

The biggest bugbear continues to be aggressive sales tactics used by staff at the pick-up desk to sell damage waiver cover – that’s insurance to cover the excess you will have to pay if you damage the car in any way. The policies sold by the rental desk often cost more than the rental itself and turn a bargain into a rip-off.

Savvy customers who are aware of these high charges, and who have bought much cheaper stand-alone excess reimbursement policies from insurers, still find themselves being manipulated into paying up for the rental outlet’s insurance. They are told their own insurance does not provide adequate cover, and that they will be on their own if they have an accident or their car breaks down. If that doesn’t work, the agent’s next ruse is to claim that the credit card handed over as security for the €1,200 deposit has been declined. The only solution, the agent will claim, is for the customer to buy their top-up cover after all. Readers who contact their bank in such situations have found that the charge was never presented. Funny that.

Those tenacious enough to overcome these hurdles can find that this battle of wills recommences on returning the car. The agent will ask “Did you buy our insurance?” Say no and you’ll find the car given a bodywork inspection that would earn praise from Sherlock Holmes.

Companies make nearly all their profit from extras sold at the pick-up desk Credit: Bloomberg Finance LP/Matthew Lloyd

Inevitably there will be a scratch – often on the underside of a bumper or the edge of a wing-mirror – that isn’t noted on the vehicle condition diagram. A smile from the rental agent at last: she’s about to hit her sales target by charging you €600 for “damage” you probably didn’t cause, knowing that you will probably be reimbursed by your excess insurer.

“Remember when you bought a new cooker or a washing machine and the shop gave you the hard sell to buy an extended guarantee? That’s what’s happening in the car rental business now,” says Kevin Bonner-Williams from Worldwide Insure, which sells excess reimbursement policies. “Companies make nearly all their profit from extras sold at the pick-up desk.”

The latest wheeze – and one that is not covered by excess-reduction policies – is to charge for cleaning the interior of the car.

When reader Andriy Kukharuk returned a car he had hired in Venice, the check-in agent said it was too dirty and a cleaning charge would apply. “It was just some dry sand in the footwells,” he says. “I was told the charge would be €40-€100 but my credit card was debited for €150.”

Another ruse is to charge an administration fee for sending damage paperwork to customers, sometimes as high as £60. Again, not all excess policies will pay these fees.

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In short, the CMA is doing a decent job at making companies and brokers clean up their act at the first point of sale. But it has proved powerless in addressing the dubious practices at the point of pick-up.

If the industry is going to restore its reputation for decent, honourable customer service, it is here that it needs to get its act together.

In the meantime, here is our guide to avoiding the stress of being overcharged by your car hire company this summer.

Car hire checklist: 20 top tips

Before you book

1. Book as far ahead as possible for the best deal.

2. Check the levels of Collision Damage Waiver (CDW) and theft protection excesses. If they are high it is definitely worth taking out zero-excess cover. Compare the cost of the broker’s own top-up waiver with an independent excess reimbursement policy.

3. If you buy an excess reimbursement policy from a broker make sure it is in the same name as the lead driver on the rental voucher otherwise it may not pay out.

4. The cost of adding extra drivers, and hiring child seats can be high and varies hugely so shop around.

5. Check the Driving section of the AA’s website (theaa.com) for advice on local driving regulations.

6. Make sure you have enough capacity on your credit card to stand a hefty deposit. Debit cards are not accepted because they have no pre-authorisation facility to ring-fence funds to cover damage.

7. Always enter the correct start time for the rental. If your flight is delayed by more than one hour you must let the rental office know otherwise your reservation may be cancelled, as cars are only held for two hours at busy times.

At the car hire desk

8. Make sure the credit card to be used is in the name of the lead driver on the rental voucher, otherwise you will have to pay again.

9. Suppliers sometimes claim the card has been declined if you have refused their insurance. Have a second card handy to put paid to this scam.

10. If you reject the local CDW top-up cover, the agent may try to sell you the Roadside Assistance cover covering vehicle recovery in case of breakdown, getting locked out, flat battery and misfueling. A UK excess reimbursement policy should cover this but not all do.

11. Once the contract is issued read it carefully before leaving the office, especially items that have been ticked as “accepted” or “declined”. If there are charges you don’t understand ask about them. If the total shown is more than that printed on your voucher you may, unwittingly, have signed up for optional insurances you do not need. You must dispute these items immediately otherwise you will have to pay for them.

Before you drive away

12. Check the fuel type (it should be noted on the agreement). Putting in the wrong fuel is regarded as negligence and all CDW cover is withdrawn.

13. Inspect the car thoroughly, make sure every tiny scratch is marked on the contract. As well as bodywork, you should check the windscreen, wheel hubs, the underside of bumpers and the edges of wing mirrors.

14. Open the boot and check that it has a warning triangle, high-visibility jacket, spare bulbs and any other items legally required in that country (the AA’s website will tell you what these are) otherwise you may be charged for their loss.

15. Use your phone or camera to take photographs of all four sides of the car.

16. Check the clutch is not burning out. To do this, put the car into fourth gear, depress the clutch and slowly let it out while stepping on the accelerator. If it releases fully without stalling, ask for another vehicle.

17. If it’s too dark to inspect the car, go over it with a fine-tooth comb the following morning and report any further scratches, noises or mechanical concerns immediately. Note the name of the person you speak to.

A good car rental firm will provide cover if, for example, the car is damaged by driving over a rock on a bend in the road Credit: pitrs - Fotolia

If you have an accident

18. Call the police if another vehicle is involved – even if the damage is minor. Fill in the legally-binding European Accident Statement form that all cars are required to carry in Europe. It will be in the local language so it’s wise to print off a UK translation before you leave from www.cartraveldocs.com. The form is split into two sections and each driver fills in their version of events. If you sign the report without ticking any of the boxes in section 12 you are effectively agreeing to the other driver’s version of events.

When you return the car

19. Keep the receipt from the petrol station where you filled up the car on the final day. Always try to get the vehicle signed back in. If this is not possible make sure you take a new set of photographs to prove it has been returned without new damage.

20. If you cannot resolve a dispute with a car rental company in the UK use the British Vehicle Rental and Leasing Association’s conciliation service (bvrla.co.uk). For disputes over rentals in the EU contact the European Car Rental Conciliation Service (ecrcs.eu).

Key questions

What does CDW really cover?

Collision Damage Waiver (CDW or LDW in the US) does not equate to comprehensive car insurance as we know it in the UK – even when it is advertised as “fully comprehensive”. A waiver is a contractual term where the rental company waives its right to claim compensation from the customer for damage to the rented vehicle. The consumer will still be liable to pay a hefty “excess”, often as much as £1,500… or even more.

As the wording implies CDW is principally designed to cover damage caused in a collision with another vehicle and not single-vehicle damage. In the past, both types of damage would have been covered – as long as the driver had not been particularly negligent. Today, as budget car rental firms look for savings, the scope of CDW cover has shrunk and new exclusions hide in the small print.

A good car rental firm will provide cover if, for example, the car is damaged by driving over a rock on a bend in the road, or if it skids on an oily road and hits a wall; a cheapskate company will try to claim negligence on the part of the driver and charge for the full cost of such damage, which can run into thousands of pounds.

In any event, the basic CDW cover usually excludes damage to tyres, wheels, wing-mirrors, windows, hubcaps, the undercarriage and roof of car. It also excludes towing costs in the case of breakdown and clutch failure – even if you have only driven a few miles.

Basic CDW cover usually excludes damage to tyres, wheels, wing-mirrors, windows, hubcaps, the undercarriage and roof of car Credit: ©AllCanadaPhotos.com

Should I use a broker?

The majority of problems arise when the reservation has been made via a car rental broker advertising low prices on price comparison sites. The broker is only a sales agent; the customer’s contract is always with the car rental company at the destination. When things go wrong many brokers just wash their hands of the problem and tell customers that they must deal with the rental agent direct.

There are a lot of new players in the online car rental game, including airlines and European-based online travel agents. It is always best to book direct with the UK website of a major car rental company, preferably a member of the BVRLA (bvrla.co.uk), European Car Rental Conciliation Service (ecrcs.eu), or with one of the better-known specialist brokers which have reasonably competent after-sales customer service teams, such as Auto Europe (autoeurope.co.uk) and Holiday Autos (holidayautos.co.uk).

Should I buy an excess reimbursement policy in the UK?

These top-up policies are designed to refund excess CDW and theft protection charges levied by the car rental company. Cover bought at the time of reserving the car is often provided by an insurer in the UK and not by the car rental agency in the destination. This is why the supplier will still need a deposit on a credit card (if you buy its own top-up waiver no deposit should be necessary). Some agents pre-authorise an amount, ring-fencing it so it cannot be spent elsewhere; other providers process the deposit payment and refund it after the car is signed back in – often at a poor exchange rate.

If damage occurs, the rental company deducts the estimated cost from the deposit held. There is usually a standard charge per scratch or ding. To be reimbursed you must obtain an estimate of the cost of repair from the supplier – often difficult to extract – and lodge a claim with the insurer in the usual way.

If you are renting a car for a week or more it is cheaper to buy a separate annual excess recovery policy from an insurance broker: moneymaxim.co.uk offers a comparison chart of cover limits. Exclusions can hide in the small print, so check it carefully – insurance4carhire.com, worldwideinsure.com and icarhireinsurance.com are among specialists with a good reputation. A stand-alone excess recovery policy costs around £40 a year for rentals in Europe which compares very favourably with top-up cover bought from the supplier’s rental counter, which can be as high as £15 a day.

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Should I have to pay for an upgrade?

Pick-up desks often try to sell you an upgrade to a bigger car. In the United States, in particular, agents will try to persuade you to upgrade saying the trunk (boot) is too small for your luggage. Refuse all attempts to get you to accept an upgrade and make sure an upgrade charge isn’t sneaked on to the paperwork you sign, as it can double the cost of your rental in the US. No reputable rental company should ask you to pay for an upgrade if it can’t provide the vehicle model you have booked.

If you have a complaint against a car rental company you may be able to seek redress through arbitration. For rentals in the UK contact bvrla.co.uk; for EU rentals contact ecrcs.eu