The building I live in is in the process of being sold. According to law the new owner has to uphold any current leases. However, I have two special circumstances, the first is that the building is owned by a cooperative, and I haven't found any laws pertaining to cooperatives (to figure out if they would be exempt from this law). This makes for a second special circumstance, the owners of each unit actually lease the apartment from the cooperative and then sublease to their tenants. I am wondering if the rules are different for subleasers.
Additionally, the lease between the owner and the cooperative states that the cooperative has the right to terminate the lease to the owner because of sale of the property. Does this make my sublease void?
If the answer is yes, how long do I have before I would have to move out after the sale is finalized?
The new company has already sent letters to all tenants giving us 15 days to decide to sign a new lease with them (without any dates specified!), and if we do not we must move within 15 days of the final sale. (and yet, when asked, they refuse to say when that might be). Any help would be appreciated!

