It has emerged that buying goods through Amazon Marketplace deprives you of a key consumer protection. When you make a payment it goes to Amazon, which subtracts its commission and sends it on to the retailer. This means that you don't make any payment direct to the retailer.
This, in turn, means that you're not covered by the Consumer Credit Act if something goes wrong.
The Consumer Credit Act is a vital tool-of-last-resort for consumers left out-of-pocket by a retailer. Section 75 makes the credit card provider jointly liable with the retailer, as long as the purchase cost between £100 and £30,000. It means that as long as you pay with a credit card, if the retailer goes bust, fails to provide the goods, or provides something faulty and refuses to replace or repair it, you can claim the money back from your card company.
However, The Guardian reported over the weekend that it had come across a number of customers of Amazon Marketplace who had tried to use this act to get their money back from Amazon Marketplace and been told that the way the purchase works on the site means that they don't have this protection.
A spokesman for the Financial Ombudsman explained to AOL: "It's to do with the set-up of Amazon Marketplace. One of the caveats in section 75 is that there has to be a direct link between the person with the credit card, the card provider, and the retailer. Amazon Marketplace puts an extra layer into this, so there's no direct link and the act doesn't apply."
Ironically, if consumers had bought direct from the sellers, rather than going through Amazon, they would have this protection.
He adds that it's important to note that this only applies to the Amazon Marketplace and not Amazon.co.uk itself. He also says that if you check the terms and conditions on the site, Amazon makes this clear. However, it doesn't stop consumers falling foul of the rule - and the Ombudsman has had to reject a handful of cases where consumers tried to use the Consumer Credit Act with Amazon Marketplace.
Amazon highlights that it offers separate protection to consumers, the Amazon A-to-Z Guarantee. A spokesman told AOL: "The Amazon A-to-z Guarantee provides additional protection for customers who buy from Amazon.co.uk's third party Marketplace."
"Amazon guarantees purchases from third party Marketplace sellers when payment is made via the Amazon.co.uk website in accordance with our A-to-z Guarantee Policy. This covers an item received being defective, damaged, not as described or received late.
If the item is not delivered, not as described or faulty, then Amazon will arrange a refund. However, this must be done within 90 days of the order being placed.
It's definitely worth bearing in mind if you are planning to make an expensive purchase from the site. If you decide to go ahead, it will be vital to check the goods carefully within 90 days before your rights elapse.
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Amazon Marketplace: key consumer protection void
Using a mobile phone to make and receive calls, send texts and browse the web while abroad can be extremely costly – especially if you are travelling outside the European Union (EU), where calls can cost up to 10 times as much as at home.
To avoid high charges, Carphone Warehouse suggests tourists ensure a data cap is in place, use applications to check data usage, turn off 'data roaming', avoid data-intensive applications such as Google Maps and YouTube and use wi-fi spots to update social networking sites.
Payment Protection Insurance (PPI) is supposed to help people to continue meeting their loan, mortgage or credit card repayments if they fall ill or lose their jobs. However, policies are often over-priced, riddled with exclusions and sold to people who could not make a claim if they needed to.
At one point, sale of this cover - which was often included automatically in loan repayments - was estimated to boost the banks' profits by up to £5 billion a year.
Now, though, consumers who were mis-sold PPI can fight back by complaining to the bank or lender concerned and taking their case to the Financial Ombudsman Service (08000 234567) should the response prove unsatisfactory.
It could be you, but let's face it, it probably won't be. In fact, buying a ticket for the Lotto only gives you a 1 in 13.9 million chance of winning the jackpot.
With odds like that, you would almost certainly be better off hanging on to your cash and saving it in a high-interest account.
No-frills airlines such as EasyJet may promote rock-bottom prices on their websites. But the overall fare you pay can be surprisingly high once extras such as luggage and credit card payment fees have been added - a process known as drip pricing.
Taking one piece of hold baggage on a return EasyJet flight, for example, adds close to £20 to the cost of your flight, while paying by credit card increases the price by a further £10.
It may therefore be worth comparing the total cost with that of a flight with a standard airline such as British Airways.
Cash advances, which include cash withdrawals, are generally charged at a much higher rate of interest than standard purchases.
While the average credit card interest rate is around 17%, a typical cash withdrawal of £500, for example, is charged at more than 26%.
What's more, as the interest accrues from the date of the transaction, rather than the next payment date, costs will mount up even if you clear your balance in full with your next payment.
Supermarkets such as Tesco and Asda often run promotions under which you can, for example, get three products for the price of two.
However, it is only worth taking advantage of these deals if you will actually use the products. Otherwise, you are simply buying for the sake of it, which is a waste of your hard-earned cash.
Buy a train ticket at the station on the day of travel and the price is likely to give you a shock - especially if you are travelling a long distance at a busy time of day.
However, you can cut the cost of train travel by 50% or more by going online and making the purchase beforehand - especially if you book 12 weeks in advance, which is when the cheapest tickets are on sale.
Other ways to reduce the price you pay include avoiding peak times and taking advantage of so-called carnet tickets, which allow you to buy, for example, 12 journeys for the price of 10.
Most High Street banks offer packaged accounts that come with monthly fees ranging from £6.50 up to as much as £40, with a typical account charging about £15 per month.
Various benefits, such as travel insurance and mobile phone insurance, are offered in return for this fee. But whether or not it is worth paying for them depends on your individual circumstances.