If you want to have a nice looking finish that will last mare than a day, then you really need to sand it.
If the existing paint job on the car is perfect already, and all you want to do is change the colour, I'd use some 800 then 1000 grit paper very lightly. Be sure that ALL dust is removed (alcohol works well) before painting.
Paint in a dust free environment
Use resiprator and paint suit.
A sandblaster or sanding disc
For pure sanding of bondo or metal, No. If you are preping to paint or sanding primer you should use Wet or Dry sandpaper and sand wet.
if you are trying to remove paint from the outer body of the car and you are looking to paint it. then start by sanding the outer body down to the bare metal then use your primary then first coat then second coat of paint
Paint stripper. Works for both metal and wood for a car sand otherwise surface contaminants will take longer to remove than sanding painting combined.
Yes you can repaint a car body there is prep work invalved with sanding and fixing rust and dents then there is primer and then the paint
After mudding and sanding, primer is next, then paint.
All you need is good preparations: sanding and degreasing.
You really could do either or neither. If your using an epoxy primer sanding is not necessary. If not you could wet or dry sand whichever you prefer. Wet sanding makes for a smoother texture finish and less dust of course.
I would use a bonding primer to start out with. Most paint stores carry it. Otherwise start with a oil-based primer, after sanding and wiping clean with a slightly DAMP cloth.
Scuff sanding, that is sanding only far enough to break the gloss and produce a matt surface is not sufficient for blistered paint. If only the topcoat is blistered, it should be sanded off completely. If the primer is blistered, it must be removed too.
Powder coated outdoor furniture must be properly prepared before painting. A light sanding will allow penetration by the paint. It is advisable to wipe the furniture after sanding and before painting.
PAINT and a Car are the two obvious items. In addition, an application tool. It could be a brush but they tend to give a poor finish. Usually it is a spray gun run by a compressor. Ideally some preparation material such as emery paper or sanding paper is needed too.