Black Friday is just around the corner and with it thousands of offers on products of all kinds. This day, which will take place on 23 November, is the starting signal for Christmas shopping. This is a golden opportunity to give us a whim because the offers are absolutely dizzying. Physical and online stores lower their products to unsuspected limits so users take advantage to acquire what they need or simply want. It is true that, currently, Internet commerce has almost more followers than face-to-face sales. The convenience of acquiring items with a single click is insurmountable but how can we know if we are making a good purchase? In Disfi we have made a selection of tips not to be ripped off during this Black Friday. If you plan to make a purchase online, this is for you.