As a continuous chain from the origin of the money to the enterprise, with a document at every step: sale agreements, corporate records, tax filings and bank statements together, rather than a bank balance and a covering letter.
The chain is only as good as its weakest link
Hypothetical example: Léa is selling a physiotherapy clinic she owns near East Ferris and will fund an EB-5 investment from the sale proceeds, a registered savings account and a loan secured against her home. Three sources means three chains. The clinic requires the purchase agreement, the closing statement, the corporate minute book showing her shareholding, and years of tax filings reporting the practice's income.
The savings account requires enough history to show how it accumulated, which for a long-held account may mean many years of statements. The mortgage requires the loan agreement, the appraisal, and evidence of where the equity itself came from. Every transfer between accounts and across currencies must then be visible in sequence, since a deposit with no matching withdrawal elsewhere is the single most common trigger for a request for evidence.
Léa should assemble this before selecting a project, because a project runs to a timetable and a source-of-funds file does not compress.