An investment decision, not an immigration date. Set a point by which the applicant will have confirmed nationality, fixed a budget and shortlisted actual businesses. Only then does an application schedule mean anything, and even then preparation, any consular step, government review and admission each take their own time with no promised outcome or date.
Keep deposits refundable while the questions are open
Sellers and landlords will press for commitment before the eligibility picture is complete. Where a deposit cannot be avoided, understand what triggers its return and record the answer in writing. Revisit the whole assessment if the shortlisted business changes sector, price or ownership structure, since each of those can move the substantiality and marginality analysis.
A schedule built on an unchosen business is a placeholder, not a plan. Set a date for the nationality answer that is measured in days rather than weeks, and treat everything else as conditional on it, since it is the only milestone here that is entirely within the applicant's control. After that, the sequence is a commercial one: budget confirmed, shortlist assembled, one venture selected, terms agreed subject to conditions, then preparation.
Where a seller presses for an exclusivity payment before the eligibility picture is complete, treat the request as a cost of information and price it accordingly, rather than as a step in an immigration timetable that has not begun.