It is not unusal for us to work in 3 different States in any one day. We are 11 miles from the MA border and 9 miles from NYS.
Here in Vermont we NEED an type S electrical license. They are strict on that. We have to pull a permit even to run thermostats and low voltage control wiring in a public building. Residential single family they don't mess with you. New thing now is if we change a RTU we need to get a town building permit. Or to do any replacement work in a public building we need a building permit. Also in Vermont they tried to get us to get gas fitting licenses but that never got off the ground.
In MA we need a Mass. AC contractors license. But we can't do gas piping, condensate drains or wiring. They look the other way on t'stats and low voltage because electricans get confused after you get past the black and white wires.
NY is the easiest. Like it was said above it goes by towns. The smaller the town the less regulations. We service Hoosic Falls NY. You can figure from there.
Actually since we, the contractors, get along in these 3 neighboring communities we kind of got our own little government and the inspectors work with us. "No hackers are allowed" in our little tri-state mafia.
For the sake of discussion let's say a mandatory state wide profiecy based HVACR license that is recognized by all local jurisdictions. After institution and the necessary grandfathering, all entering the trade must complete some form of apprenticeship period then test for journeyman license then futher down the road for a master license. Of course recognizing formal programs such as the UA provides.
Don't let your ego get in the way of a good decision
Here in NC I have a state license and then just about every town has their own Privilege license. It's all $50 a pop. It would be nice if the state license was enough for everyone in the state but every town wants a piece of the pie too.