Dover is a moderate-high cost-of-living market — pricing guide and permit rules below.
Dover window replacement rates: $3,000-$10,000 per system. Always get 3 written quotes and verify NH licensing at New Hampshire OPLC (oplc.nh.gov). Sales tax on materials: 0%.
Dover requires permits when work exceeds $1,000 or involves full system replacement. Your licensed contractor pulls the permit — if they ask you to pull it, that's a red flag.