The time needed to complete an exterior paint job varies depending on the size of the home, the condition of your home’s exterior, the weather conditions and type of paint used on the job. An average project lasts 3-4 days, while a complex project may take a week or more. Additional time may be needed to fix loose or damaged siding or add primer to areas without coverage. Your painter will provide a timeline that explains how long the project will last and will schedule the job to avoid inclement weather.
Oh, where to begin? Let me start with 'watered down paint'. 25-50% before the material gets to the site? Impossible. You would basically be painting with water at that point. It would be less of a hassle, and cost, to simply use proper material. You would be forced to apply three coats instead of two, as the coverage would be horrible. Whatever cost you think might be saved in materials would be lost in labor.