Having sold and shipped a lot of firearms online, I will point out that not all FFLs accept shipments from private sellers. Some will only conduct FFL-to-FFL transfers, which means you will have to go to an FFL in your area, hand over the firearm and they will ship it to the buyer's FFL. That can cost you some extra money, as most FFLs will charge you an "FFL transfer fee" in addition to some sort of shipping charge. When I do sell firearms online, I always say that I will only ship to an FFL who will accept transfers from a private sellers. In that case, most FFL's will require a copy of your driver's license (when you ship the firearm) and that will act in place of the FFL that you do not have. As always, you should always check for yourself on the legality of shipping firearms, but there is some good information on here to get you started. Also, keep in mind that you only have to ship serial-numbered items to FFLs. Gun parts, etc. do not need to be shipped to an FFL. For example, lots of people buy different parts of Assault Rifles and piece them together themselves. An upper receiver of an AR can be shipped directly to someone's front door (because it's not serial numbered) whereas the lower receiver (the serial numbered piece) has to be shipped to an FFL. Hopefully this was a bit helpful.