Q. We need to rent a people-carrier for a holiday in Switzerland. I have found a company called Honk Car Rental which promises: "We're like those mystery deals you sometimes get for hotels, but instead for car rental." Being very cautious, I follow the maxim that anything that appears too good to be true, probably is. So before paying for a car, do you know anything about them? Peter Canton, by email

A. You could book a car in Switzerland with a company based in New Zealand, but it's difficult to see why you would. Presumably you found Honk Car Rental through a price-comparison website. Here is how the business model appears to work; draw your own conclusions about whether you want to get involved.

Honk Car Rental owns no cars. It is a broker, whose parent company is located in Commerce Street, Auckland. We tested it out by asking for a quote on a five-day rental in "Edinburgh City" this week. Honk quoted £150 for a Ford Fiesta or similar. Not bad.

But the car is not actually available for pick-up in the city centre; it is supplied by the Arnold Clark depot in Seafield, three miles away. You pay a "deposit" of £21, which appears to be the company's commission; you pay the remainder to Arnold Clark when you pick up the car.

Yet if you book direct with Arnold Clark you pay a flat £135 – 10 per cent less than Honk wants. So Honk's boast, "You'll pay less than your friend who books a car with someone else", looks hollow.

Where does this leave your trip? Well, we then looked for prices for a week's hire of a Ford Galaxy or Renault Espace seven-seater at Zurich airport in June. Through a price-comparison website the quote was £767, of which the "pay now" element – which often turns out to be the broker's commission – was £200.

Same dates, same vehicle through Avis, was quoted at £838. But Hertz and Holiday Autos both came in at £472, a rate so low that it is difficult to see why you would look elsewhere. All other things being equal, it is best to book direct with Hertz because usually the fewer layers involved in a travel transaction, the better.