Across 25 permits filed since 2025-01-25, the median is $30,000; half of projects fall between $10,000 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
- Construct 60 SF front porch addition Interior alterations 1st floor, convert attic to habitable space, finished basement.Village of Garden City · 2026-07-22$115,000
- Finish basementVillage of Garden City · 2026-06-26$30,000
- Residential Piping & Fixtures- Rough and finish three-piece basement bathVillage of Garden City · 2026-06-19$4,000
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 $10,000 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