Across 31 permits filed since 2025-05-03, the median is $40,000; half of projects fall between $17,900 and $80,000. Figures are permit valuations reported to building departments. National cost guides answer this question with averages from other markets; these numbers are what homeowners in Garden City, NY actually reported when they pulled permits.
Recent filings
- Finish basement laundry roomVillage of Garden City · 2026-10-20$56,840
- Construct 474 sq. ft. first floor addition with 576 sq. ft. second floor & finished basement with a 21 SF r/o side entry , interior alterations.Village of Garden City · 2026-10-08$630,000
- Residential Electrical - Run wiring first, second floor & basement additions/ alterations including circuits, switches, receptacles and lighting components and HVACVillage of Garden City · 2026-10-08$22,000
How to read these numbers
Permit valuations are the project cost the applicant reports to the building department. They skew slightly low — nobody rounds up for the permit fee — and scope varies, so the middle-half range is the honest picture: half of all basement finishing permits in Garden City, NY came in between $17,900 and $80,000. We exclude permits under $1,000, jobs filed as whole-house construction, and counties whose building departments don't reliably report valuations.
Same project, other places
Basement finishing in New YorkBasement finishing in ConnecticutBasement finishing on Long Island