As a window cleaner too.. We Carry cleaning detergents for this. Super glean three is very concentrated so a little goes a long way. We usually have a five gallon bucket filled with clean water, some super glean 1 oz. a little rinsing agent. After we rinse the house thoroughly, we then have a man brush the glass with our mix and rinse with city water. However, water can be the issue as you know, so the end result can change with location. This is always explained up front. If our result doesn't look great, we up sell the window cleaning...winner