Owner's book · not a shop
Know the car. Then the window. Factory specs in plain English — don't authorize until you can say this at the counter.
Independent shop
Beginner · short stepsExpert · spec · code · mm
Diagnosis is a line. Supplies have a number. Authorization is a ceiling.
Fair quoting: diag split, shop supplies disclosed, authorization ceiling, no vibe approvals.
07 · Independent shop