A state will set limits on what work is allowed without a contractors license. But it's really up to each jurisdiction as to what rules are enforced.
I have seen some really big jobs ( total cost) being done without permits. In some areas they think nothing of it and others the job would probably get shut down.
the largest thing i've seen
completed here unpermitted was in pasadena area,
the electrical was about $300k.
my chiropractor did a large remodel on his offices, including moving restrooms,
saw cutting the slab to move sewers, redoing ceiling and all lighting... and his
office was next door to a building under construction, so there was building
inspectors right next door often. i cautioned him what would happen if he was
caught....
how he got caught was pretty funny. pablo or hector was washing out his mud
pan at the curb with a hose, and it was running down the street. the building
inspector next door happened to observe this, and when over to tell him he
could not do it. the offending laborer, not speaking much english, told him to
effen off.
annoyed, the inspector walked in the door of the office, and saw a full blown
construction site, with patients laying on adjusting tables, and people hanging
drywall above them.
my chiropractor got a lesson in being a chew toy for code enforcement.
tuition was above $150k.