Brokerage statements showing the account's history, tax returns reporting the income that funded it and the gains realized, the company records behind that income, and the liquidation and transfer records to the enterprise. The chain must reach back to how the money was earned.
Show how the account was built, not only what it holds
A current brokerage balance proves the couple has money; it does not prove where the money came from. The petition needs the earlier story. For a portfolio funded from a Paradise landscaping company's profits, include the company's financial statements and corporate tax returns for the years of the largest contributions, the couple's personal tax assessments showing dividends or salary drawn from the company, the brokerage account opening documents and periodic statements showing deposits that match those drawings, and tax returns reporting capital gains and dividends as the portfolio grew.
Then document the liquidation through sale confirmations, settlement into the couple's bank account, any currency conversion, and the wire into the new commercial enterprise's U.S. account. If a large deposit came from another source, such as an inheritance or property sale, document that source separately.
A short narrative with a table linking each document to a step helps the officer, and any unexplained gap can prompt a request for evidence.