prime first. It won't stick to bare plastic unless it's roughed up really good. But sticks to any flat paint really well.
Never had a case of ghosting, bleeding or etching when used properly. ,, even with the hottest House of Color lacquers.
You can get the quart like Bill posted above but it will dry up and/or rust the inside of the can before you use even 1/4 of it. or you can get it in spray cans like below but it tends to spray thick and too heavy for model work. I decant some and keep it pre-thinned with rubbing alcohol in a Tamiya bottle for air brushing. A spray can usually lasts me 5 or 6 years at 3 to 6 models a year so, yea, a can goes a long way.