Start the file now, but do not file the petition until the capital is actually received and committed. The source-of-funds evidence can be assembled while the estate is administered.
Assemble the chains during administration; file when the money has landed
Hypothetical example: EB-5 requires that the capital be invested or actively in the process of being invested at filing, so a Portugal Cove-St. Philip's investor cannot file on the strength of an expected distribution. The waiting period is not wasted: the executor can be asked for the estate accounts and the deceased's financial history while administration continues, the pension commutation can be elected and the transfer completed, and the regional-center subscription documents and TEA evidence can be reviewed. Once the distribution arrives, the transfer to the enterprise should follow promptly and by wire, so that the path from receipt to investment is short and clean. Filing before the funds have landed invites a denial or a request for evidence; filing long after they arrive, with the funds sitting in the investor's account, invites questions about why they were not committed. The priority date is the filing date, so once the capital is in hand, delay only costs queue position.
Hypothetical example: an optometry-practice owner has funds ready but expects to sell the practice before relocating permanently. The person should compare three separate timelines: source-and-path documentation, petition processing and visa availability, and the planned move or sale. The project subscription and transfer records show when capital was committed; the personal records show whether the investor can maintain the intended residence plan. An approval at one stage does not eliminate the later process for an immigrant visa or an adjustment, so a sale contract should not be timed on an assumed arrival date.