Keep three buckets apart: capital actually committed and at risk in the U.S. enterprise, business transaction costs such as deal negotiation and valuation, and immigration-preparation costs. How a particular expense is treated depends on the facts, so ask for the reasoning rather than assuming that every professional fee counts or that none does.
Ask how each expense is treated and why
There is no fixed minimum figure; substantiality is judged against the cost of the enterprise being acquired or created. Document what has been spent, what is irrevocably committed, and what remains contingent on closing. Escrow terms and refund or revocation clauses need fact-specific review rather than a blanket label. Confirm any government charges at the time of the relevant step instead of relying on a figure quoted earlier.
Identify the lawful source and path of funds actually committed and the genuine treatment of any customer payments. Identify what the valuation measures and whether any royalty or maintenance obligations remain with the enterprise. Substantiality is proportional to the cost of this particular business, and the amount must be enough to make the investor's commitment credible. Professional fees for the purchase and the application are private costs to budget separately.