Effectuer des paiements ponctuels et envoyer des factures

Add a one-off payment and invoice flow for [SERVICE OR PRODUCT]. This is not a subscription and must never create a recurring charge.

Offer [PAY NOW / SEND AN INVOICE / BOTH]. The price is [PRICE] in [CURRENCY CODE]. The description customers should see is [PLAIN-LANGUAGE DESCRIPTION]. Use [PAYMENT PROVIDER] in its test environment until I approve going live.

For Pay now, show a clear order summary before checkout with the item, quantity if relevant, price, currency, what the customer receives and my refund or cancellation policy [POLICY]. Send the customer to the provider's secure checkout so this app never stores card details. If they cancel or payment fails, return them to the app with a clear message and do not mark anything paid or deliver the item.

For invoices, add an owner-only action that creates an invoice for [CUSTOMER NAME AND EMAIL] with [LINE ITEM DESCRIPTION], [PRICE], [CURRENCY CODE], [DUE DATE] and [OPTIONAL NOTE]. An invoice is a request for payment, while a receipt confirms that payment happened. Send the customer a secure provider-hosted link where possible and show the invoice as unpaid until the provider confirms payment.

After a confirmed payment, show a thank-you page and send the customer a confirmation containing [WHAT THEY BOUGHT], [AMOUNT AND CURRENCY], [PAYMENT DATE], [ORDER OR INVOICE REFERENCE], [WHAT HAPPENS NEXT] and [SUPPORT CONTACT]. Give them access to a provider receipt or paid invoice. Notify [OWNER EMAIL] without including full card or private payment details.

Save a readable status for each order or invoice: pending, paid, failed, cancelled or refunded. Confirm payment with the provider before changing the status, sending a paid confirmation, reserving a time or releasing a download. Refreshing the success page or receiving the same confirmation twice must not fulfil the purchase twice.

Do not invent tax rates, invoice wording required by a particular country or accounting claims. Use [BUSINESS DETAILS], [TAX INFORMATION SUPPLIED BY ME] and the payment provider's settings. Flag anything that needs a local accountant or legal review.

Keep the checkout calm and trustworthy, matching [BRAND STYLE]. Test a successful payment, a cancelled checkout, a failed payment and a repeated page refresh. Tell me what the customer receives in each case and what I must do before accepting real money.