This is the one we use on the homepage, because it shows exactly what a proper clean does. Weeds in every joint, moss across the shaded side and years of traffic film had turned a red herringbone driveway a flat grey-brown.
Weeds out first, then the rotary surface cleaner across the whole area, hand-lanced edges, and kiln-dried sand brushed back into every joint. The colour that came back surprised the owner as much as us.