"You should only take out a store card to get a discount if you can repay all the money when you get your first statement, as this means you avoid paying any interest," Mr Saville commented.
"If you don't plan to do this, avoid taking out store cards altogether."
He went on to say that finance companies should make sure that they don't give consumers store cards with credit limits beyond their repayment ability.
"Financial institutions should always lend responsibly and properly assess the consumer's ability to pay back the credit extended," he added.
"Consumers should also not be unduly pressurised or incentivised to take on additional debt."
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