The Code of Practice for Determining Employment or Self-employment Status of Individuals (pdf) contains criteria which can be used to clarify whether a person is employed or self-employed. In most cases, it is clear whether a person is an employee or not.
The 708 area code belongs to the state of Illinois (IL) and some of the locations covered are Cicero, Oak Park and more:
The 707 area code belongs to the state of California (CA) and some of the locations covered are Santa Rosa, Vallejo and more: