The escrow agreement and its release conditions, bank records tracing the transfer path, the executed purchase agreement, and evidence of expenditure already made in the business such as equipment, deposits and payroll.
Read the escrow before signing it
An escrow that returns the funds to the buyer if the visa is refused is the standard arrangement and is compatible with the capital being at risk in the relevant sense. An escrow with wider release conditions, allowing the buyer to withdraw for other reasons, weakens the position. Read the clause rather than accepting a description of it. Alongside the escrow, assemble the transfer path: statements showing where the money originated, each account it passed through, any currency conversion, and its arrival. Where funds came from the sale of a Canadian asset, include the sale documents and the resulting deposit. Where any part is borrowed, show the loan agreement and what secures it, since capital secured by the assets of the United States enterprise itself is treated differently from a loan secured on the investor's own unrelated property.
Hypothetical example: A specialty-bakery purchaser has bank statements, a seller's brochure, and a verbal plan to take over next month. The first review should turn those into a source-and-use record: lawful-source documents, transfer records, signed purchase terms, equipment lists, lease details, and a business plan tied to actual numbers. The purchase agreement settles what is being acquired; a wire confirmation settles money movement; an operating licence or lease can help settle that the enterprise is real. Do not rely on a seller's projected revenue without reconciling it to tax returns, invoices, or financial statements. The evidence must show funds committed and exposed to business loss, not merely available.