Sequencing is fact-specific. Capital generally must be irrevocably committed and at risk, which points toward a signed and funded arrangement; escrow structures conditioned on the visa outcome need individual review. Discuss the sequence with counsel before wiring money or agreeing to a closing date.
Set milestones rather than a promised start date
Fix dates for due diligence, segment financials, funding documentation and packet review, then decide the closing timing. Leave room in the purchase agreement for the possibility that no application is approved, since no processing time or outcome is guaranteed. Remember too that a visa's validity period is not the same as the authorized stay recorded on the Form I-94, which matters when planning the transition period with the seller.
Nothing in the application makes sense until ownership and control are fixed, so the operating agreement is drafted and signed first, with an execution clause tying the transfer of the half-share to visa issuance. Useful milestones include the date each installment clears, the date the enterprise account is funded, the signing of key contracts, and the completion of the source-of-funds file. The accepted way to reconcile these is an escrow whose release is conditioned only on visa issuance, so that the money is out of the buyer's control and the deal completes automatically on approval.