Original 1880s–1900s Brooklyn brownstone structural shells reclassify poorly, but post-2000 renovation pools are where the cost-seg math actually lives. Engine-derived walkthrough at $1.85M Park Slope with $500K renovation pool.
Before the analysis: the underlying numbers this post draws on come from 5 New York City-area properties run through the Cost Seg Smart engine, same engine that produces real customer studies. Median Year-1 federal savings is $27,167 at the 37% top marginal bracket with 100% bonus depreciation. Reclassification ratio ranges 11.4% to 18.5%.
Let's start with the regulatory reality: NYC is not a short-term-rental investor market. Local Law 18 (effective September 2023) requires every short-term rental in New York City to register with the Office of Special Enforcement, restricts STR operations to two-guest stays in the host's primary residence with the host physically present during the rental, prohibits whole-unit STR for non-primary-residence operators, and requires structural compliance with specific building-code provisions. The practical effect: absentee STR strategies that work in Joshua Tree, Tahoe, or Gatlinburg do not exist in NYC. The §469 short-term-rental loophole is structurally unavailable for the typical...
The remainder of this section drills into the specifics that matter for regulatory specific. The five fixtures we ran through the engine for New York City span $685,000 to $1,850,000 in purchase price across 5 distinct sub-markets, enough variance to draw real conclusions about which scenarios actually produce cost-seg ROI in this market.
Take the Park Slope Brownstone LTR as our anchor example. Purchase price: $1,850,000. Built 1890, 2800 sqft, SFR, located in Brooklyn pre-war (Park Slope / Brooklyn Heights / Cobble Hill).
The engine determined land allocation of 44.8% using statistical methodology, producing a depreciable basis of $1,021,015. Of that, the engine reclassified $94,636 into 5-year personal property (FF&E, decorative finishes, certain electrical), $68,425 into 15-year land improvements (paving, landscaping, hardscape, site lighting), and the rest into the 27.5-Year Residential Real Property structural category.
That produces a total reclassification ratio of 16.0%. At 100% bonus depreciation and a 37% federal marginal bracket, the illustrative Year-1 federal tax savings is $60,333. That's the headline number for this fixture.
Contrast that with Manhattan Condo Rental: $1,485,000 in Manhattan condo (mid-tier), built 2014. Here the engine produced a reclassification ratio of 12.2%, lower than the previous example.
Why? Two reasons. First, the land allocation profile is different, 60.0% here versus 44.8% for the previous example. Second, the engine's treatment of condo interacts with the build-year and FF&E density differently across neighborhoods.
The takeaway: in New York City, the per-fixture variance is real. A median number (16.0% reclass) hides meaningful variation across sub-markets and property archetypes.
New York partially decouples from federal §168(k), NY has historically required an addback for federal bonus depreciation, with the addback recovered over the regular MACRS schedule for state purposes. NYC has its own local income tax stacked on top. For 2025+ acquisitions under OBBBA's 100% federal bonus, NY-side timing impact is meaningful given the high state-plus-local rates. The federal §168(k) acceleration is unaffected; the state-and-city-side reconciliation is the variable.
Decoupling: NY has periodically modified bonus depreciation conformity. Verify current-year treatment with your CPA. NYC's local income tax is separate from state but applies on the same federal-adjusted base.
This affects every cost-seg calculation in New York City. Because New York doesn't fully conform, the federal Year-1 figure shown above is only the federal-only portion. The state benefit is smaller (or different) and your CPA will need to manage the addback at filing time.
Local Law 18 (effective September 2023) is the most restrictive STR ordinance in the United States. STR operations in NYC require registration with the Office of Special Enforcement, are limited to the host's primary residence with the host present, prohibit whole-unit STR for absentee operators, and require structural compliance with specific building-code provisions including window egress, fire safety, and density. Practical effect for cost-seg planning: the §469 short-term-rental loophole is unavailable for typical absentee NYC investors. Cost-seg works in NYC for long-term-rental investment, fix-and-flip, and small-multifamily operations under standard §469 passive-loss rules. Real-estate-professional status under §469(c)(7) is the typical path to active-deduction treatment for high-volume NYC operators. Combined NY state plus NYC local income tax reaches ~14.8% top marginal, with partial decoupling from federal §168(k) creating state-and-city-side timing mismatches that should be modeled explicitly in CPA workflow.
To run this analysis for your specific New York City property: the same engine, with your address, year built, square footage, and renovation history. Studies start at $495 for residential under $300K. Audit defense is included with every Cost Seg Smart study.
To run this analysis for your specific New York City property: the same engine, with your address, year built, square footage, and renovation history. Studies start at $495 for residential under $300K. Audit defense is included with every Cost Seg Smart study.