You will see that almost every card or loan is now 'representative APR', meaning just 51 per cent of accepted applicants get the boasted-about rate, the rest pay more. Worse, to learn your rate, you must usually apply and that hits your credit score.
Yet, Nationwide's 6.7 per cent representative APR for those borrowing £7,500 to £15,00 (6.6 per cent for its Flexaccount customers), is not only the market's cheapest loan, but it also uniquely uses a quotation-search that doesn't mark credit files, so it tells you your exact rate before you formally apply (although you may still be rejected). So, if the rate is not good enough there is no need to carry on with the application.
But remember, you should only get new debt if you really need to. Keep it as low as possible and repay as quickly as possible. Also, check you have budgeted to ensure it is affordable. See www.moneysavingexpert.com/loans