Want a hotel room but can't be bothered to search the multiple reservation sites? The new breed of comparison sites, such as Trivago, Kayak and Travelsupermarket.com, promise to do the shopping around for you. But a Guardian Money price check has found that no single site produces guaranteed best prices – and that travellers should check all three before buying. Trivago is spending millions on a TV advertising campaign where a couple search for a room in Barcelona. "We compare over 100 websites to find your ideal hotel at the best price," says the voiceover. But despite promising to find the best price, some of the comparison sites lead holidaymakers into paying significantly over the odds. Get the full story at the The Guardian