>>27729697i've been an 07ffl for about 6 years now (started as an 03, then 01, then 07). you will never make a living off of doing that unless you have some serious skills.
if you perform the tasks in a single day and nothing is mailed to you, you do not need any ffl do to any of that.
if you need to retain the firearm for more than a day, you typically need to book it in then book it out when the job is done. that requires an ffl as that is a transfer.
>>27729740"more than trigger jobs" covers a lot of stuff. gunsmithing is a skilled multi-disciplined job that involves metal working, wood working, parts-swapping (simple handyman stuff), and general research and mechanical aptitude. certain specialized skills may be needed as well. most smiths charge between $50 and $200 an hour, and you're lucky if people are willing to do $75 and hour.
don't think about comparing it to some desk job either; with all the overhead you might be making a little under half that as take home, which wont get you rich, but you'll be making a living.
a lot of people balk at paying $150 for a smith to time and shim a revolver, but bitch when they can't do it themselves.