A two-story wood-frame duplex on Martense Street in Flatbush is on track to become a six-story, 49-unit apartment building, according to permits filed with the city. The site, located between Bedford and Flatbush avenues, currently holds a two-family home built in 1930, but the new filing outlines a much larger residential future for the 4,176-square-foot lot.
The permits, first reported by New York YIMBY, list 73 Martense 123 LLC as the owner behind the application. The proposed building would rise 73 feet, include a cellar and a penthouse, and yield 33,340 square feet of residential space with a concrete-based structure. Based on the average unit scope of roughly 680 square feet, the outlet reports the residences are most likely to be rentals.
No demolition permits for the existing residential structure have been filed yet, and the report notes that no estimated completion date has been announced. Elliot Ambalo is associated with 73 Martense 123 LLC, and Oleg Ruditser, who works for Engineering Professional Service P.E., is listed as architect of record for the project.
Zoning Allows the Jump From Duplex to Dense Rental Building
The scale of the change is striking on paper: NYC Department of Finance property records show the current structure measures just 2,660 square feet on its lot, a modest wood-frame duplex dwarfed by the 49-unit plan now filed for the same parcel. That leap is possible because the lot sits within an R7A contextual residential zoning district, according to Redfin, a designation that permits medium-density Quality Housing apartment buildings under strict height and lot-coverage rules without requiring a zoning variance.
The property's sale history underscores how quickly land values have moved in the area. PropertyShark records show the lot sold for $718,289 in December 2025, after 36 years under the same ownership dating back to a $22,500 sale in January 1989. The site also scores a 100 out of 100 “Rider's Paradise” rating from PropertyShark for transit access, sitting less than 0.3 miles from both the Church Avenue B/Q and Church Avenue 2/5 subway stations — a proximity that supports higher-density housing with minimal parking needs.
Developer and Architect Carry a History of Scrutiny
Elliot Ambalo has drawn outside attention before. The Real Deal reported in July 2023 that Ambalo was the focus of investigative reporting, alongside outlet THE CITY, examining real estate acquisitions tied to fractional inheritances and eviction proceedings in Brooklyn. A year later, News 12 Brooklyn reported that housing activists and community coalition members staged a public demonstration targeting Elliot and Joseph Ambalo, calling for legislative protections against predatory real estate practices.
The architect of record, Oleg Ruditser, has his own regulatory history. A May 2020 enforcement bulletin from the NYC Department of Buildings noted that Ruditser had undergone an audit revealing major code non-compliance issues across multiple professionally certified project filings. More recently, New York YIMBY reported in December 2025 that Ruditser was named architect of record for a separate proposed project, a 65-foot-tall, 10-unit mixed-use building at 5622 14th Avenue in Borough Park, suggesting continued involvement in outer-borough infill housing.
Part of a Wider Flatbush Redevelopment Pattern
The Martense Street filing fits a pattern playing out across the neighborhood. Flatbush is home to more than 60,000 residents with a median age of 36.9, according to Census figures compiled by Point2Homes, a dense population base that continues to drive demand for new housing near transit. Just this month, swaps one house for 23 rentals at a nearby East Flatbush site, where permits were filed to replace a single-lot parcel with a 23-unit building near subway service.
Whether the existing duplex at 73 Martense Street will come down soon remains an open question, since demolition permits have not yet been filed. It is also unclear whether Brooklyn Community Board 14 or local residents will raise questions about the project once it moves through further public review.
