Estimating the number of windows in New York City requires making several assumptions and calculations. We need to consider both residential and commercial buildings. First, we'd determine the total land area of NYC and then estimate the proportion of that area occupied by buildings. Next, we'd break down the building space into residential and commercial categories. For residential areas, we'd estimate the average number of windows per dwelling unit (apartment or house) and multiply that by the estimated number of dwelling units. For commercial buildings, we'd estimate the average number of windows per square foot or per floor, considering different building types (offices, retail, etc.), and multiply by the total commercial building area. Without specific data on building density, average dwelling size, and window counts per unit/area, any number would be a rough estimate.