Hempstead is a very high cost-of-living market — pricing guide and permit rules below.
Hempstead window replacement rates: $5,000-$18,000 per system. Hempstead's freeze-thaw cycles stress systems. Always get 3 written quotes and verify NY licensing at New York DOS (dos.ny.gov). Sales tax on materials: 8%.
Hempstead requires permits when work exceeds $200 or involves full system replacement. Your licensed contractor pulls the permit — if they ask you to pull it, that's a red flag.