Twelve floors up, a terrace lawn catches the last of the sun as it drops past the Hudson, and for a few minutes the city below turns amber. Flawless Reflections LLC keeps green spaces like that one in shape — mowing, trimming, edging, and the seasonal cleanups that keep a planted space from going ragged. Ground at that height is unforgiving: wind pulls at it, sun bakes it, and it needs someone on a schedule rather than someone in an emergency. The payoff is stepping out a door in July onto something soft and even, forty feet above the traffic. Manhattan, with service across the surrounding boroughs.