Back in the days before e-commerce, every job was billed using paper invoices, everyone was paid with paper checks, and all those paper records were delivered in person or sent in the mail. Back then it was easy to put together the information needed for an invoice. For the self-employed freelancer in the 21st century, things are no longer that simple and it affects what you put on your personalized invoices.
It does not get any easier than this. A simple invoice is ideal for small businesses or individuals who want simplicity and flexibility. Enter a service description, calculate the total, and you’re done. If you don’t need to charge tax, just set the tax rate to zero percent.