I Ihaven't done this in almost 3 years, So I am kinda in the loop of things when it comes to prepin a car for paint. I've searched the website for info and could only find one thread that talked about using 320grit Is this true???

I don't want to remove all the paint. I just want to basically rough up or remove the clear coat that is on the car, and prime the vehicle with a flat black or a primer grey color. Any suggestions please.

It's not a car worth spending several hundreds or thousands of dollars to repaint the car. Just want the car too look more decent on the outside again.