There is one single thing that they ask. It all depends on the circumstances in which you got your account limited and they will tell you what they need. If it is in regards to your identity then a utility bill and govt issued photo id may be required. If it is in regards to the credit card you added then the credit card statement may come into play. If it is in regards to what you sell then they may ask you for the shipping documents, invoices and probably proof of stock.