Coop Term of Lease

I'm confused. I thought you were purchasing an apartment next to the one you already own,to combine, talking to architects, engineers, etc.

All the proprietary leases expire 50-100 years, for example, after the co-op was formed. The board or shareholders periodically vote to extend the leases. Quite a bit in google about it, re: what happens if they don't, etc.

To check whether the co-op owns or leases the land, use ACRIS to find the co-op's name, then search on that. Either a deed, a lease, a memorandum of lease, and/or mortgage docs will turn up. The language in the co-op's mortgage docs will be clear as to whether the land is owned (e.g. "fee simple") or leased ("leasehold interest".)