I wish it was that simple. I have multiple surfaces to cover, stains, small amounts of rust, clean new shiney metal, old scraped metal and painted surface all on this one ceiling. 2000 sq ft of fancy molded tin ceiling. I can't find one primer that has a rust inhibitive, stain blocker, sticks to glossy surfaces,all in one. Once I find the right primer, I can paint with any paint.... Thanks for all of your help.