Every home has details that can be accentuated for amazing looking visual appeal and first impressions. The key is to not make the wrong details stand out. Entryways, windows, shutters and other details on the home can be painted to make their design noticeable. However features such as gutters, downspouts, external air conditioning systems, unevenly proportioned windows and protruding garage doors should not be completed to draw attention to them as this will provide a negative results.
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.