Drivers can pay up to seven times more if they buy car hire excess policies direct from the hire firm and not from a third party, new research has revealed.
Car hire drivers normally pay a set amount, or excess, if their vehicle is crashed or stolen. Excess waiver deals are a form of insurance that covers this cost.
But these vary hugely in price.
For example, hiring a Seat Leon car from Hertz vehicle hire at Barcelona airport for eight days would cost £253.47, and the excess waiver would be £189.93.
Hiring a Seat Arona from hire firm Budget at Malaga airport would cost £264.83, with the excess waiver being £180, plus an extra £66 if you needed to claim.
An Avis Seat Leon hired from Alicante airport would cost £183, and the excess policy would be £175.88.
But the same deal for any of these cars would be just £27.96 on the open market, according to comparison website TravelSupermarket.
This is 14pc of the price of the Hertz deal, 15.3pc of the cost of the Budget policy and 15.8pc of the Avis option.
Car hire firms tend to sell excess waivers at their counters and not in advance online or on the phone.
The Telegraph has previously reported how unscrupulous car hire staff taking advantage of the pressure caused by long queues to coerce drivers into buying their insurance.
Emma Coulthurst, of TravelSupermarket, said: "The lack of transparency suggests that the companies are wanting you to not compare policies before your trip but be sold the policies at extortionate amounts, once you’ve arrived tired from your journey and are a captive audience."
An Avis Budget spokesman said: "Customers are always welcome to use their own providers if they so wish. In addition, for complete transparency, we encourage all customers to review items and charges highlighted in the contract before signing, and to ask our highly trained rental agents if they have any questions."
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