521 Dean Street
521 Dean Street, between Carlton and Sixth avenues · Prospect Heights
BBL 3011280076 · BIN 3027629
- Year built
- 1930
- Type
- Prewar walk-up
- Landmark
- No
Every recorded sale at this building, 2004–2025
Bedroom-by-bedroom medians, the full transfer record, and how units trade against ask.
- 2BR median
- $913K
- Recent range
- $510K – $950K
- Listing discount
- 1.1%
- Recorded transfers
- 25
Own an apartment here? See what it would sell for.
A Private Pricing Opinion — what your apartment at 521 Dean Street would likely sell for today, what it costs to sell, and what you’d walk away with — reviewed personally against condition, exposures, renovation quality, and the competition actually on the market.
521 Dean Street is a ten-residence cooperative with more layout variety than its four-story scale suggests. The building includes conventional one- and two-bedroom apartments, lower-level duplexes and a top-floor duplex with a private roof deck. Its broad frontage accommodates rooms across a wider span than many narrow rowhouse conversions in Prospect Heights.
Architecture and unit composition
The building occupies a frontage of approximately 28.5 feet. It is a walk-up with apartments distributed across four floors. City records date it to 1930, and the cooperative conversion was accepted in January 1990 and became effective that November.
The ten-home filing covers a rehabilitated building converted to cooperative ownership. Its subsequent apartment configurations include both single-level homes and duplexes. Some two-bedroom plans have a separate half bath, and a second bedroom can function as a dining room when a purchaser prefers more living space.
The upper duplex type combines two bedrooms with an additional den and two bathrooms. Its private roof deck is reached from within the home. Lower duplex configurations extend living space across two levels at the base of the building. These homes differ in stair arrangements and in how their rooms receive light; an advertised extra room should retain the legal use shown on its approved plan.
Building operations
521 Dean Street Owners Corp. is self-managed. Apartment owners therefore deal with a board-led operating structure within a ten-residence building. Intercom access and stair circulation are the principal shared entry arrangements.
The building has no landmark designation. Its existing floor area exceeds the residential floor-area ratio now allowed by its R6B zoning. The current building envelope is therefore an important constraint for any proposal that would add enclosed space, including an enlargement connected to a roof-level apartment.
Recent sales
Recent transfers at this building, curated by The Roebling Team research desk. Prices are the transfer amounts recorded with the NYC Department of Finance; apartment-level detail is checked against the building’s own file in The Roebling Research Library before publishing.
| Date | Unit | Apartment | Price | vs. Ask |
|---|---|---|---|---|
| Oct 23, 2025 | 2 | 1 BR · 1 BA | $690,000 | +0.7% |
| Mar 10, 2025 | 6 | 2 BR · 1.5 BA | $925,000 | +0.0% |
| Feb 12, 2025 | 5 | 2 BR · 1.5 BA | $900,000 | -2.2% |
| Feb 12, 2025 | 1 | 1 BR · 1 BA | $510,000 | -7.1% |
| Aug 5, 2024 | 7 | 2 BR · 1.5 BA | $950,000 | +2.7% |
| Jul 17, 2023 | 5 | 2 BR · 1.5 BA | $851,000 | -4.3% |
| Sep 13, 2022 | 2 | 1 BR · 1 BA | $680,000 | +2.3% |
| Aug 18, 2021 | 4 | 1 BR · 1 BA | $800,000 | +10.3% |
Market read. Median listing discount 0.0% from the last ask.
The retrade record
Lines that have traded more than once in the public record — the building’s appreciation arc, apartment by apartment.
Full closing history with price-per-square-foot over time, the complete retrade record, and every line that has traded.
Sales sourced from NYC Department of Finance recorded transfers (BBL 3-01128-0076) and verified listing data. Apartment-level facts (line, condition, asking-price context) curated and cross-verified by The Roebling Team research desk. Not all transactions cross-verify with ACRIS records — sponsor and LLC purchases sometimes record at stipulated values rather than market price.
What to know if you’re buying
A private roof deck sits within a shared building. The upper duplex's outdoor area creates a specific boundary between exclusive use and cooperative responsibility for the underlying roof. Establish which repairs belong to the apartment and which belong to the corporation, including responsibility for removing and reinstalling deck surfaces when the roof needs work.
Comparable buildings
- Sterling Atrium — A small prewar cooperative for comparing ownership at a similar scale.
- 149 Lafayette Avenue — A similarly sized prewar cooperative with a taller building form.
- 60 South Oxford Street — A close match in cooperative tenure and low-rise scale.
- 147 South Oxford Street — A larger prewar cooperative for buyers comparing a broader apartment inventory.
- 904 Union Street — A small prewar cooperative offering a Park Slope location alternative.
More Prospect Heights buildings
- 430 Sterling Place — 1908 co-op
- 436 Sterling Place — 1908 co-op
- 50 Plaza Street East — 1925 co-op
- 543 Dean Street, 543 Dean Street · Prospect Heights — condominium
- 55 Eastern Parkway — 1925 co-op
- 550 Vanderbilt Avenue — 2015 condominium
The neighborhood
For the full neighborhood — its buildings, character, and market — read The Roebling Team Guide to Prospect Heights.
The full playbook — what goes in the package, how boards read your financials, the interview, and the timeline — plus sample cover, reference, and personal letters you can adapt.
How to read the facts on this page. Items attributed to an offering plan describe the building as it was offered at that filing — unit mix, square footage, the amenity program as planned. They are not a statement about how the building operates today. Tax and compliance figures are sourced separately to current City records and carry their own dates. House rules, staffing and fee policy can change by board resolution without any public filing: treat every policy line here as a starting point for diligence and confirm it with the managing agent. Where this page compares one building or neighborhood to another, that is our analysis of the recorded record — it names the measure, the period and the sample it rests on, and it is an observation about medians rather than a prediction about any particular apartment.
Considering a move at 521 Dean Street?
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