Utilities and big landlords handle overhanging limbs and disputed lines hundreds of times a year. The habits that make that work are mostly free to copy.
The wage is the smallest number in the calculation and the only one most owners run. The rest of it decides whether the hire works or quietly drains the year.
Licensing quietly settles who can treat you, who pays, and where a complaint goes. Here is how to tell the license from the certificate before the first appointment.