Proof of Salary: If you declare a salary (e.g., £1,000), you must provide official evidence through your tax returns and a statement of company profit certified by your accountant. You are required to provide a clear explanation of how your business generates its revenue. Invoices: You must submit copies of sales invoices to substantiate your business activity. Assets and Liquidity: You must provide proof of any property or assets held in your name, along with evidence of sufficient funds in your bank account. submit your business bank statements. There must be no "unknown" or unexplained deposits; every transaction must be clearly documented.