An unbroken documentary path from the lawful origin of the money to the enterprise: statements for each account the funds passed through, evidence of how the money was earned or realized, and the closing documents showing it reached the seller.
A path, not a balance
The common misunderstanding is that a bank statement showing a sufficient balance proves the investment. It does not. What is being established is that the funds are the investor's own, lawfully obtained, and irrevocably committed to the enterprise. For savings accumulated from a practice, that means several years of tax filings and financial statements showing the income that produced them. For a term deposit, the maturity documents and the transfer out. For a property sale, the sale agreement, the statement of adjustments and the deposit of proceeds. Every intermediate account matters, including any joint account or a currency-conversion account, because a gap in the chain invites the question of whose money it really is. Finally, the closing statement, the bill of sale and evidence of payment to the seller show that the commitment actually happened rather than being planned.
Hypothetical example: A Canadian greenhouse-components supplier buys a small U.S. fabrication shop using proceeds from a family-held corporation. The document review should trace the money before it reaches the purchase account: corporate resolutions, dividends or sale records, tax filings, bank statements, currency transfers, escrow instructions, and closing payments. The question is both lawful source and actual commitment. A spreadsheet that skips an intermediate account can make legitimate funds look unexplained. The enterprise must be treaty-owned, and the investor's money must be irrevocably committed and subject to commercial risk, not simply reserved for a possible future transaction. The first reviewer should draw a dated flow chart, then match every arrow to a record. That sequencing reveals gaps before an application depends on an affidavit to explain them.