Airport parking could hurt your wallet more than a flight, according to a new study by Which? Travel magazine.
The new report says that if you are not organised, drive to the airport and don't book your parking in advance then you are going to get, well, royally stung.
According to the Daily Mail, the magazine says that the only way to keep prices down at all of the UK's 13 most visited airports is to book early.
The study found that prices can more than double if you just turn up looking for a spot to leave your car for the week.
At Birmingham's long-stay sites it is possible to pay £28 for a week but, if you don't have a reservation, that price shoots up to £85.
At Stansted, the cheapest price will be the Long Stay Extra Supersaver, but that is only available if you book more than 30 days before take-off.
A spokesperson for Which? Travel told the Daily Mail that car parks outside the airport could be a better bet, saying:: "Glasgow International airport's cheapest deal was nearly twice the price of Airparks, four miles away.
'Off-site car park deals will include shuttle transfers, and these can be as quick as from the airport's own cheapest car park. Check what security the car park has before you book, though.
"In some cases, official airport car parks may be cheaper as we found at Birmingham, Luton and Stansted. If you want to keep your car within the airport grounds, booking direct via the airport's website is usually (but not always) just as cheap as going via other retailers."
Booked in advance, a week's parking at Heathrow costs £66 but turn up on the day and you'll be paying £120.
At Gatwick, an organised holidaymaker will pay £41 for a week, while a disorganised one will shell out £91.
Up at Manchester, if you book early you can get away with paying £35.99, but if you don't you'll be £100 lighter.
Airport parking isn't the only thing that could end up costing you more than your flight if you're not careful.
According to moneysupermarket.com's travel expert Bob Atkinson, a family of four could pay up to £191 more for their insurance if they buy it at an airport location on the day of deprture.
And, if you're not careful, you could pay £145 more than you need to for car hire on a walk-up price instead of a pre-booked option.
Bob says: "In general, the earlier you book the larger the savings can be on your rental, so don't just take the option offered to you by your travel agent, tour operator or airline. In general they only sell one company, and so do not check the entire market for the best prices."
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