Write down where and how your first customers will pay: at a counter, at their table, at a market, online or in advance of an appointment. Then list your opening date, connectivity, number of staff and the equipment already in place.
Ask prospective providers what documents they need, what approval is required and when the equipment can realistically be ready. A delivery estimate is different from confirmation that an account is approved and working. Allow time to test a sale and refund, train staff and check where payouts appear.
Think about what happens when a device loses power or the connection drops. Ask about permitted alternatives and avoid promising customers a payment method that you have not tested. Keep the contract, support contact and pricing schedule somewhere you can find them quickly.
What type of business are you opening, and what is the one payment question you need answered before the first day? Share an approximate opening date rather than private application documents.