Facebook advertising has no fixed Belgian click price or monthly budget that makes sense for every small business. You set a budget, but what it produces depends on the audience, objective, ad and destination page. A cheap click is useful only if it supports a relevant enquiry or customer outcome.
Start by calculating what an enquiry can cost, then choose a limited test budget. Facebook and Instagram share Meta's advertising environment, but you should not assume that their results are identical. Every amount below is an illustrative calculation, not a Belgian market average or promised result.