I have never seen the siding so clean here. The previous contractors left large swathes of blackened siding behind the maple trees in the fronts of units, as well as on the large north-facing wall of siding in the central area. Retro is making those missed areas vibrantly clean. Also, I noted that Alan and his crew are very particular and careful about small patches of dirt, bird droppings and such, actually scrubbing them off, which is more than anyone else has done before. From what I can see, we've never had such good performance from a cleaning contractor in the 20 years I've been here. Thank you.