Some automotive websites recommend using compressed air to remove dust & debris from interior crevices, or to remove dust, debris or water from exterior crevices & cavities. I think that can be potentially harmful to the body and requires a bulky/expensive compressor or expensive canned air.
On the body, using compressed air could be damaging, by forcing dirt into the paint, or lifting/breaking paint or rust off the metal, or blowing abrasive particles across the paint. I wondered if there was a less-powerful source of compressed air, besides canned air to do the job.
Something like a hand-powered air pump with a rubber tip? Could you convert a spray bottle to pump air?
thxZ