As a simple rule; install only the ones you need, and whose failure you would immediately notice. If nobody cares, the numbers provide no value anyway.
You're never really comparing like with like, because the value is realized through avoided costs, not income, and every building plot is slightly different.
From cutting costs to engaging with customers... the right temperature, clean towels locked and loaded and a signature standard of quality, adds bottom line.
They’re compact, low-profile, and visually/structurally urban compatible. Maintenance can happen at ground level, without a cherry picker and a prayer.