Hi I’m due to have the exterior of my house painted but would like some advice as to which paint to choose. It has rough rendering on the walls. Also the cills have a metal edging which is rusting. What is the best solution to stop this coming through and what paint is best to have if painted white? I just don’t want it to be spoilt by coming through shortly after it’s done. I have photos I could send if you give me an email address. Many thanks