GOt to weigh in, on this one.
Dad has owned multiple car dealerships, gas stations and, yes, body shops.
Best friend had a body shop, for decades, until his knees went bad and good help got to hard to find, Luckily, he had enough money to say, Done.
I, personally, have done all the body work , from yanking off dented parts, to frame replacements, to final spray, on over a hundred cars. Some less than a year old to high dollar classics.
Paint is Paint. Don't care if it comes from a industrial grade air gun, wal-mart airless or a rattle can. If you can get the same paint, in each of the applications, lay it on "wet" and it will look good "Dry".
Tools are just that, tools.
No difference, to the nail, which hammer you use, the $2 walmart special, nice framing hammer or air hammer. nail still gets nailed. Only real difference is ability of person doing the job.
Tools can make the job, easier but, in the end, its all about the skill level.
AS regards Professional.... Even Da Vinci was an Amateur, until he started to get paid, regularly. More importantly, not every Professional, of the Era, was a Da Vinci.