I keep hearing the term (skin inspection), the only skin inspections are the obvious smoking rivit and phase inspections done for corrosion from the inside (usually bildge and lav/galley areas that are prone).
The only exterior surface inspection i know of was the lap seam (i said was) as they have been done away with, with exception of a few classic aircraft. The ironic part is that lap seam inspections are suspect to at least one catastrophic failure, lap seams have to be aerodynamically filled with a compound usually the same that seals in fuel tanks, this is some tough stuff. it is supposed to be removed with a non-metallic tool. Years of suspect usage of metallic tools to cut this junk out cut the seam and eventually created a explosive seperation (aloha 737).
Back on point, paint does not make inspecting aircraft skin much harder than it is W/O it.