It is possible that two weeks of occupancy, with or without a written sublease, does not equate with a landlord-tenant relationship with the sublessor.
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You have a landlord - tenant relationship. Pursuant to NY RPAPL 711, a tenant shall include "an occupant of one or more rooms in a rooming house or a resident, not including a transient occupant of one or more rooms in a hotel who has been in possession for thirty consecutive days or longer...."
Puruant to your question, you have been in possession for more than 30 days. Furthermore, you have paid money to the landlord for the possession. Therefore, you are a tenant.
However, even if you were not considered a tenant, the "landlord" would have the responsibility to return the deposit.
Attorney Markowitz hit the nail on the head!
Moreover, even if there were no Landlord-Tennant Relationship there would still be a contract issue (perhaps quasi-contract if there is an insufficient or no writting). The person you sublet from has retained money for which there was no exchange of any good or service. In either event you have a valid claim at law.
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