
Do I need to create a shipping
invoice if I'm mailing documents
to you from within the U.S?

No.
If you’re shipping your legal documents from anywhere inside the U.S to us, and/or we are mailing your documents back to you within the U.S you won’t be required by FedEx, UPS, or USPS to create a shipping (customs) invoice like you have to do the majority of the time when you ship documents internationally.