In other words, can anyone just decide to open a locksmith’s shop tomorrow, or do you need some kind of licence to do it? On the one hand, it’s a typical blue collar job, but on the other hand they have tools that can give them unauthorised access to other people’s premises.
This is yet another case of it varies by state or even locality. Most states don’t regulate.
There are certified and bonded Locksmiths, but if you don’t know what you’re looking for, these mean little. As with most things in life beware bait and switch deals.
As to the tools, I have most of the tools a locksmith has and have installed, rebuilt and rekeyed quite a few locks. The few tools I don’t have I can buy legally online.
Not sure about pick sets but most locksmiths don’t actually use these, at least for most work.
The YouTuber The Lock Picking Lawyer has all sorts of tools he sells. You’d think they are illegal but apparently not (and since he is a lawyer I am willing to bet he checked).
Weirdly fun videos to watch too. You would not think so but they are.
I won’t link anything here except his YouTube channel…I am not trying to push sales. All this can be easily Googled.
About ~46 states allow possession of lock picks, and you can generally use them if the lock or location is your property or you have permission to do so. Either they make it explicitly legal or do not mention it.
About 4: NV, OH, VA, MS don’t strictly state it’s illegal, but it may be a prima facie situation - if you are detained and have tools on you, you may get charged even if there is no evidence you intended to use them nefariously. In other words, it’s probably not a good idea to include them in your everyday carry items. In the other 46 it would only be an issue if caught in the act or with evidence.
Some states put strict requirements on licensing if you do it for money as a professional locksmith, and in the 4 mentioned above a license is a good way to show likely innocent intent. Presumably a conviction would also cause you to lose your license permanently.
Most consumer grade locks are not hard to pick (with some notable exceptions) but can be fiddly, for the most part a professional locksmith does not pick locks with a tool and a tension bar. And criminals are rarely debonair safecrackers compared to someone smashing a window.