The minimum and maximum amounts you can buy and Sell coins for is set by them. The page will then redirect you to your credit card payment page. The first time was just a demo kind of thing, a way to get to the registration page! The speed might be influenced by your country , mode of payment and certain other factors, so make sure you dig deep enough and get a clear picture of exactly how long the coins would take before arriving in your wallet. It has a user-base of over 6. But if you were simply going to buy Bitcoin using some other Cryptocurrency, it only requires the cell-verification from you.