Enough to be substantial in proportion to the total cost of acquiring or establishing this kind of business, and committed irrevocably rather than held in reserve. There is no published minimum that applies across industries.
Commitment is judged by proportion and by irreversibility
Hypothetical example: the couple hold back a large reserve because it feels prudent, and the file then shows a modest committed amount against a substantial purchase price. Prudence and the requirement pull in opposite directions here, and the resolution is usually to structure the transaction so that the committed portion is clearly identified and genuinely irreversible, with operating reserves held and described separately. Do not add future lease payments, projected payroll or planned advertising to the invested amount; those are operating expenses.
Do include the purchase price, equipment, inventory, deposits and any franchise or licence transfer costs actually paid or unconditionally obligated. Government amounts for the application itself are published by the responsible agency and are small relative to the transaction. Budget separately for legal, accounting and cross-border tax advice.