Size alone does not decide it. The requirement is that the enterprise not be marginal — that is, not one existing only to provide a living for the investor and family. A small business with employees, or with a documented capacity to generate more than a minimal living within a reasonable time, can be assessed on that basis.
Ask what the business does besides pay its owner
Work through the question concretely rather than as an abstraction. How many people does the company employ, and would it still employ them after the sale. What does it earn after the owner has been paid a normal wage for the work performed. Does it hold contracts that continue past the closing date, or does the revenue follow the departing owner personally. Those answers describe whether there is an enterprise or simply a job with equipment attached. Where the present picture is thin and the argument rests on future capacity, the plan supporting it has to be specific and evidenced, because the assessment is made on the record filed rather than on the applicant's confidence. A licensed adviser should see the financial statements before anyone forms a view.
Hypothetical example: Dario, a specialty-coffee roaster, has signed a lease but has not yet placed the equipment order. He should compare the enterprise’s total cost with the money already committed and identify which obligations expose him to commercial loss. A cancellable lease plus cash left in his personal account may show preparation, not a substantial at-risk investment. The ownership record must also establish treaty nationality and his ability to develop and direct the business. Before applying, he needs evidence that the enterprise is real and capable of operating and that its plan is not marginal rather than a paper vehicle supporting only his household.