[2rsf]

> I issue invoices only after a successful payment, because I owe tax on all invoices including unpaid

(IANA I am not an accountant) but how is it legal? as a customer you want to pay against an invoice, and AFAIK it is required by law in most places.

[jwr]

You pay against a proforma invoice, or if your credit card gets charged automatically, there is no proforma and you just get an invoice that confirms the transaction.

But in general, this is why proforma invoices exist.