Paint depends on the project,
Figs, I use Testors Acryl and usually spary it with an airbrush.
For dios or other surfaces I will use a wide variety of paints. On compatable items I always hit it with a primer surfacer, on items like my swamp speeder where I built from wood, bondo and other hard surface items I use a heavy fill surfacer to get rid of any imperfections. I do use premium auto body items, since I have them in my shop already, as for the color. I will use anything from cheap spray cans to model paints. Testors is my prefered brand for brush on paint, simply becasue I can get it at a Hobby Lobby right down the road from where I work.
I will also seal most items with Deft semi gloos, flat or gloss poly depending on final project goals.