The first deadlines
A summons in New York sets a short period to respond, and the exact length depends on how the papers were served. Letting that period pass can result in a default judgment without any hearing on the merits. If the plaintiff has filed a notice of pendency, your ability to sell or refinance may already be affected, and a notice filed without a proper basis can be challenged. Some contracts require mediation or arbitration before any lawsuit, which can change where the dispute belongs. These questions come before any discussion of who is right. If you received papers at a property you rarely visit, or long after they were apparently served, mention that early, because how and when service happened can matter.
Coverage and records that may help
Before paying for a defense yourself, check whether someone else may owe it. An owner's title insurance policy may cover the defense of certain claims against title, such as a boundary or easement dispute, and homeowners or commercial liability policies sometimes respond to claims of property damage. Notify the insurer promptly and in writing, since late notice can complicate coverage. Gather the contract or lease, closing documents, survey, title policy, emails with the other side and any brokers, and anything showing payments made or received. Keep everything as it is and do not delete messages, even ones that look unhelpful.
Deciding the shape of the defense
A flat denial is not always the right answer to a claim against you. Some cases call for counterclaims, for example where the other party failed to close or misdescribed the property, and some are better resolved early through a negotiated exit. A real estate defense also looks at leverage: what the plaintiff actually needs, such as a closing, a payment, or a clean title, and what it would cost each side to keep litigating. In an initial review we go over the complaint, the response deadline, the insurance picture, and your goal for the property. From there we sketch a plan that matches the stakes.