The activity history and posts made by this account are the characteristics of a scammer. He tried in the lending section, and then exchanged Bitcoins, offering services and now he promises to sell you a mystery box that will be shipped to your home address. Mystery Box was a popular content on YouTube, but now it has become a thing of the past, I think. With shipping costs included, the $10 Mystery Box will be an empty box (if it arrives to you).