Dear New York Commercial Garage Landlord:
Lease drafting is among the most important business activity of any property owner, and does not lend itself to information from the Internet, or to use of do-it-yourself forms.
Your attorney would review with you various forms for commercial leasing and riders specifically drafted for use with stand alone parking garages, and requirements, if any for registering the garage as a business, incorporating the ownership of the garage property to control aspects of liability, filing an assumed business name, securing a permit from the NYC Department of Consumer affairs, as well as other matters that will come to light in a face to face private and confidential legal consultation.
The answer provided to you is in the nature of general information. The general proposition being that you should try to avoid a bad outcome if you can.
In addition to what Mr. Smollens wrote, you may run into serious legal problems in the case of a garage tenant. The value of the tenant is nothing that the tenant's added to the promise or improved it in some other way. The lease is only valuable for the cars that are parked in it. In NY it is not uncommon for garage tenants to have long-term leases. If it is your intent to confiscate the cars that are in the garage pursuant to leases, you could be charged with grand larceny, theft, fraud, and any number of other crimes..
Your analogy to self-storage units is misplaced. With such units, the lessees own the contents (or have a claim to them). Cancelling the leases for these units would give you access to property owned by the tenants of such units. By comparison, your garage tenant does not own the cars in the garage, so you cannot have any claim to them.
I urge you to speak to an attorney before you try to play lawyer yourself. You'll be in a heap of trouble if you don't.
I am an attorney admitted solely in NY. None of the answers I submit on this forum constitutes legal advice, even to questioners in NY, and no attorney-client relationship is hereby created.