I tried searching here but I didn't get any suitable result. He e-mailed me a PDF copy of the sporting goods store/dealer's license. I verified through atfonline.gov/fflezcheck that the license is valid and it matches the address. His instruction is to send the shotgun with a photocopy of my driver's license with his info as the recipient to the FFL dealer. Can I ship it via regular UPS or USPS just like any other package?

P.S. I bought the shotgun from Caso's in Jersey City and it's not that far of a drive but since I'm selling it for $150 shipped I want to save money if I can just send it directly to his FFL. Everything good? Thanks in advance.

You may ship a long gun to a licensed dealer using either the USPS, or a common carrier (UPS/FexEx).  So long as his receiving dealer is OK with receiving a firearm from a non-licensee (and it sounds like he is - as that's where the copy of the license and the instructions to include your DL most likely came from), you're all set.

Reference USPS Domestic Mail Manual 601, section 12.3:



Be prepared to reference this should the counterperson at the post office give you any grief.

I was in the post office on Thursday.

...burp.

Looks like you've done everything correctly.
Keep a copy of his FFL with the guns serial number.