The walkaround: what a good detailer checks before quoting
A serious detailer does not quote a paint correction from a photo. The first diagnostic is a paint depth gauge — a small ultrasonic or magnetic device pressed against each panel that reads total paint thickness in microns. Factory paint typically reads 100–160 microns. A panel reading 250 microns has been resprayed; a panel reading 80 has probably been machine-polished hard before and has little clearcoat left to work with. Correcting paint means removing clearcoat, so knowing how much remains is the difference between a safe polish and striking through to the colour coat.
The second check is contamination. The detailer runs a hand — often inside a thin plastic bag, which amplifies texture — across the paint. Paint that feels gritty rather than glass-smooth is carrying bonded contamination: industrial fallout, brake dust particles, tar, and in the UAE, mineral deposits from hard water and the occasional cement overspray from the construction site next door. None of that comes off in a wash, and polishing over it drags the particles around, so it dictates a decontamination stage before any machine work.