Buying inspection: rust hot spots and the magnet caveat

Prospective buyers press for photos of rockers (inside and out), wheel-well frame members and the undercarriage as the potential corrosion points, and are wary of thick underbody coatings hiding repairs. The 'magnet trick' is debated: sellers use it to argue panels are solid, but experienced buyers caution a magnet reveals body filler, not rust, since much corrosion hides below the surface.