Hi, I want to try and get my boat painted this month on a DIY/budget basis. I have been advised to use marine paints (some other residents haven't) and I will be sanding the smooth unbroken parts and electric sanding as close to bare metal as possible the rusty and broken parts. I may be selling so it's largely cosmetic. I was planning to use red oxide where there is currently rust and where the previous layer has come off and where the steel is bare. * Do I need then to use a primer/undercoat or can I just do two coats of topcoat on top of the red oxide? * The boat is is 22x4 M and has 5 1M windows both sides and 2x 3 smaller windows. The sides are mostly OK to over-paint and it's the decks/walkways/roof that needs the most attention re. the rust and paint damage. The top half of the hull is a mixture of OK and rusted and obviously needs topcats. Approximately how much paint etc will I need so I can roughly cost it? Thanks for your attention Brian