521 HENRY STREET is a prewar 1900 building, 4 units in Carroll Gardens, NYC. Owned by 2023 O'CONNELL QSS TRUST. Public records show 7 open violations, 23 311 complaints on file.
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Asking rent per bedroom type — switch tabs to see each with effective (concession-net) rent.
Brooklyn · February 2026
Best & worst months to sign a lease
Potential savings: ~13% by timing your move to August.
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View full landlord profileTop 5 by score · of 11 total
HPD Class A Violation — (A) § HMC:FILE ANNUAL BEDBUG REPORT IN ACCORDANCE WITH HPD RULE AS DESCRIBED ON THE BACK OF THIS NOTICE OF VIOLATION OR
HPD Class I Violation — §27-2107 ADM CODE OWNER FAILED TO FILE A VALID REGISTRATION STATEMENT WITH THE DEPARTMENT AS REQUIRED BY ADM CODE §27-20
HEAT/HOT WATER — APARTMENT ONLY
Monthly counts over the last 7 years · all data sources
ACRIS deeds and regulatory filings
Noise - Residential — Loud Television
Noise - Residential — Loud Music/Party
HEAT/HOT WATER — ENTIRE BUILDING
HEAT/HOT WATER — ENTIRE BUILDING
HEAT/HOT WATER — ENTIRE BUILDING
HEAT/HOT WATER — ENTIRE BUILDING
HEAT/HOT WATER — ENTIRE BUILDING
(A) § HMC:FILE ANNUAL BEDBUG REPORT IN ACCORDANCE WITH HPD RULE AS DESCRIBED ON THE BACK OF THIS NOTICE OF VIOLATION OR AS DESCRIBED ON HPDS WEBSITE, WWW.NYC.GOV\HPD, SEARCH BED BUGS.
§27-2107 ADM CODE OWNER FAILED TO FILE A VALID REGISTRATION STATEMENT WITH THE DEPARTMENT AS REQUIRED BY ADM CODE §27-2097 AND IS THEREFORE SUBJECT TO CIVIL PENALTIES, PROHIBITED FROM CERTIFYING VIOLATIONS, AND DENIED THE RIGHT TO RECOVER POSSESSION OF PREMISES FOR NONPAYMENT OF RENT UNTIL A VALID REGISTRATION STATEMENT IS FILED.
§ 27-2031 ADM CODE PROVIDE HOT WATER AT ALL HOT WATER FIXTURES IN THE 1st ROOM FROM NORTH LOCATED AT APT 1, 1st STORY, 1st APARTMENT FROM EAST AT SOUTH
§ 27-2070 ADM CODE PROVIDE AN ADEQUATE SUPPLY OF GAS TO THE FIXTURES AT RANGE IN THE KITCHEN LOCATED AT APT 1, 1st STORY, 1st APARTMENT FROM EAST AT SOUTH
(A) § HMC:FILE ANNUAL BEDBUG REPORT IN ACCORDANCE WITH HPD RULE AS DESCRIBED ON THE BACK OF THIS NOTICE OF VIOLATION OR AS DESCRIBED ON HPDS WEBSITE, WWW.NYC.GOV\HPD, SEARCH BED BUGS.
Carroll Gardens is Brooklyn's Italian-American soul — bocce courts in the community gardens, old-school red-sauce joints alongside farm-to-table newcomers, and wide, tree-lined blocks with deep front stoops that invite lingering. Smith and Court Streets have some of Brooklyn's best dining.