Los Angeles Chief's Reg 4 testing

Hello. I am new to the forum. I have been a fire alarm technician for approx. 17 years. I’ve done new installs, worked as a programmer, service technician, and most recently managed a service department. I am looking for a change, and would like to increase my value by obtaining certification to be a tester for the Chief’s Regulation 4.
I would appreciate any advice or information regarding this process. And, I would also like to get an idea of what the average hourly rate for a Reg 4 tester is.
Thanks in advance for any help y’all might have.