I used to ship FedEx, but the last time was maybe 2 years ago. Back then UPS rules were that you could only ship from a UPS distribution center. FexEx you could drop off at any FedEx store (pre-packaged, with no indication on the packaging). Reading their rules now though, and it's clear USPS is the only way to go for the casual collector (handguns are a whole different matter now compared to a couple years ago)
https://pe.usps.com/text/pub52/pub52c4_009.htm
I'm reading a whole lot of red tape that wasn't there 2 years ago, and likewise for the FedEx rules. They used to be the easiest, except for handguns. Would be an interesting exercise to use the WayBack machine and provide a direct comparison of the escalation.