Miriam Lefkowitz, Chaim Klein pay $3.3M for walkup in Williamsburg

Miriam Lefkowitz and Chaim Klein through the entity North 9 Equity LLC paid $3.3 million to Marek Kaczor through the entity 143 North, LLC for the six-unit residential walkup building (C2) at 143 North 9th Street in Williamsburg, Brooklyn. The expected use is cash flowing.
The deal closed on August 29, 2025 and was recorded on September 15, 2025. The property has 4,125 square feet of built space and 875 square feet of additional air rights for a total buildable of 5,000 square feet according to a PincusCo analysis of city data. The sale price per built square foot is $800 and the price per buildable square foot is $660 per the PincusCo analysis. (The price per square foot analysis is the transaction price divided by square feet as reported in public records and assumes no air rights have been sold.)
The signatory for Marek Kaczor was Avi Rosengarten . The contract date was April 3, 2025.

Prior sales and revenue

Prior to this transaction, PincusCo has no record that the buyer Miriam Lefkowitz had purchased any other properties and has no record it sold any properties over the past 24 months.
The seller Marek Kaczor purchased three properties in three transactions for a total of $9.5 million and sold four properties in four transactions for a total of $13.5 million over the same time period. The former owner according to the Department of Housing Preservation and Development is Marek Kaczor, individual owner. The 4,125-square-foot property generated revenue of $117,315 or $28 per square foot, according to the most recent income and expense figures.

The property

The residential walkup building with 6 residential units in Williamsburg has 4,125 square feet of built space and 875 square feet of additional air rights for a total buildable of 5,000 square feet according to a PincusCo analysis of city data. The parcel has frontage of 25 feet and is 100 feet deep with a total lot size of 2,500 square feet. The zoning is R6B which allows for up to 2 times floor area ratio (FAR) for residential with inclusionary housing. The city-designated market value for the property in 2022 is $1.7 million.

Violations and lawsuits

There were no lawsuits or bankruptcies filed against the property for the past 24 months. In addition, according to city public data, the property has received two DOB violations, $130,000 in ECB penalties, and $132,630 in OATH penalties in the last year.

Development

There are no active new building construction projects or major alteration projects with initial costs more than $1 million on this tax lot.

The block

On this tax block, PincusCo has identified the owners of 13 of the 21 commercial properties representing 96,894 square feet of the 131,869 square feet. The largest owner is Lineaire Group, followed by Manjula Mukhopadhyay and then Baudin Canka.
There are no active new building construction projects on this tax block.

The majority, or 45 percent of the 131,869 square feet of built space are walkup buildings, with elevator buildings next occupying 28 percent of the space.

The seller

The PincusCo database currently indicates that Marek Kaczor owned at least six commercial properties with 26 residential units in New York City with 21,362 square feet and a city-determined market value of $9.6 million. (Market value is typically about 50% of actual value.) The portfolio has $1.9 million in debt, borrowed from Polish & Slavic Federal Credit Union. Within the portfolio, the bulk, or 54 percent of the 21,362 square feet of built space are walkup properties, with C3 properties next occupying 26 percent of the space. They are all located in Brooklyn.

The buyer

The PincusCo database currently indicates that Chaim Klein owned at least two commercial properties with eight residential units in New York City with 7,600 square feet and a city-determined market value of $2.8 million. (Market value is typically about 50% of actual value.) Within the portfolio, all identified are mixed-use properties. They are all located in Brooklyn.

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