Jack, I think there are two things here, regarding the FFL.  One, yes, if you are going to sell numerous firearms, then you should have an FFL, or have a friend who is one.  I was told many years ago that there was a limit of how many firearms a private citizen could sell at one time without being considered a dealer.  I am not sure if that was correct, or just hearsay.  However, the other consideration here is if you are going to manufacture firearms.  I believe that is a different license from the one for selling/transferring.

Relating to last week’s caller about selling self-built guns and their labeling requirements, I didn’t like the guy saying stuff but without sourcing his info (the firearms area is soooo full of know-it-alls it’s hard to parse the crap from the actual law, so I always dmodd).  I’ve “rolled my own” without serial numbers, but have never sold or transferred one, so never looked into the requirements until now.

So, I found this:
From the ATF: Individuals manufacturing sporting-type firearms for their own use need not hold Federal Firearms Licenses (FFLs). However, we suggest that the manufacturer at least identify the firearm with a serial number as a safeguard in the event that the firearm is lost or stolen. Also, the firearm should be identified as required in 27 CFR 478.92 if it is sold or otherwise lawfully transferred in the future. 
Source: http://www.atf.gov/firearms/faq/firearms-technology.html
from here:

https://www.80percentarms.com/pages/faq.html

and then looked up 478.92, which says this:
(i) The model, if such designation has been made;
(ii) The caliber or gauge;
(iii) Your name (or recognized abbreviation) and also, when applicable, the name of the foreign manufacturer or maker;
(iv) In the case of a domestically made firearm, the city and State (or recognized abbreviation thereof) where you as the manufacturer maintain your place of business, or where you, as the maker, made the firearm;
which I got from here:

https://www.law.cornell.edu/cfr/text/27/479.102

Posting here to help others, if they want it. I note with interest, that the ATF thing says “should”, not “shall”. Not that I’d want to test that in front of a judge and paying for my own council…

Re Moving to the USA

Just because the clowns in the Beehive made a poorly thought out legislation (which some estimates say could cost taxpayers upto a billion NZD ) doesn’t mean that you should look at emigration

There is a reason that Silicon Valley billionaires are establishing themselves here on NZ. I suggest you look at the whole picture