Mr. Dishi said in court papers that he had no idea Mr. Osman and his first wife were no longer tenants, claiming the second Ms. Osman never identified herself by her first name.
The court was unbothered by the errors, and on June 13, Judge Brenda Spears of Manhattan housing court denied Ms. Tarnofsky's motion to dismiss the case. No reason was given, and Ms. Tarnofsky is appealing. Mr. Dishi's lawyers, who also declined to comment, are now seeking materials from Ms. Osman to prove she is entitled to the apartment, such as death and marriage certificates and expense accounts going back to 1991. The apartment is the only residential unit in the building.
Ms. Osman also was no fan of the previous landlord, who let the apartment fall into disrepair from New Mexico. "I never would have thought things could have gotten worse," Ms. Osman said, while sitting on a couch draped in a sheet, as are most of the other antiques and family heirlooms, to protect it from the leaky ceiling.
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Things have only gotten worse as the number of violations in the apartment have risen from 72 under the previous landlord to 201 under Mr. Dishi, city records show.
The city's Department of Housing Preservation and Development has spent $49,000 on repairs since 2005, including most recently replacing a banister, fixing the living room radiator and turning on the heat, which was off for much of the brutal winter. Mr. Dishi has been billed for the repairs.
"Two hundred violations is a lot for a single building, let alone a single apartment," a department spokesman, Eric Bederman, said. "It's clear the owner isn't keeping the building up."
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He may well have plans to put something else up instead. In 2010, Mr. Dishi paid $24.5 million for the neighboring building on the corner of 73rd Street, a medical office building once home to Dr. Ruth Westheimer, the sex therapist. By tearing down both buildings, he could build an apartment building at least twice as large on a prime Upper East Side corner, though it would require special city approvals since it is part of a historic district.
Mr. Dishi has said Ms. Osman is herself looking to cash in. "She explained that she was interested in moving back to her homeland, which I think is in the Ukraine, and for a 'significant' amount would be willing to go," he said in court papers.
Ms. Osman, while offended by the geographic lapse, said she was open to a deal. "It pains me to leave, but he must be reasonable," she said. "I am accustomed to a certain lifestyle, and he cannot just throw me out."
—By Matt A.V. Chaban, The New York Times