At a glance
Firm: Cornerstone Management — the New York City co-op and condo manager operating as Cornerstone Management Systems, Inc. Role: Managing agent for Manhattan residential cooperatives and condominiums, with a focus on small and mid-size buildings Type: Full-service New York City residential property manager Official website: cornerstone-ny.com — see the About and Buildings pages Status: Active managing agent as of this writing Source: The Roebling Team at Compass — compiled from public records and building records on file. July 2026.
Who Cornerstone Management is
Cornerstone Management is a New York City residential property manager — operating as Cornerstone Management Systems, Inc. — that acts as managing agent for Manhattan cooperatives and condominiums, with a stated focus on small and mid-size buildings. The firm markets full-service management covering financial oversight, maintenance coordination, and day-to-day resident administration.
Note on identity: "Cornerstone" is a common name across unrelated property firms in and beyond New York, so confirm you are dealing with the Manhattan co-op/condo manager (Cornerstone Management Systems / cornerstone-ny.com) and the exact contracting entity in the building's documents. Independent public documentation is limited beyond the firm's own materials, so figures its marketing cites should be confirmed rather than assumed.
Common diligence questions
These are the questions we ask on a buyer's or seller's behalf when a building is managed by Cornerstone Management. They are prompts for diligence, not claims about this firm's practices — answers vary by building and change over time.
- Contracting entity: Is the building's managing agent contracted as Cornerstone Management Systems, Inc., and who is the assigned property manager and senior point of contact?
- Board-package turnaround: How long is management currently taking to review a completed purchase application and schedule a board interview, and what is the realistic window from submission to a closing-ready approval?
- Access to financials, reserves, and minutes: What financial statements, current budget, reserve position, and board-meeting minutes will management release to a purchaser's attorney, and how quickly?
- Responsiveness and staffing: Who is the assigned property manager, and how is on-site staffing structured (resident manager/superintendent, door staff) versus what is handled off-site at the management office?
- Closing, waiver, and move-in handling: How does the agent process the waiver/recognition of the right of first refusal, closing scheduling, and move-in coordination, including any deposits, fees, and required lead time?
- Assessments and capital projects: Are any current or anticipated assessments, Local Law 11/facade, elevator, or mechanical projects on the books, and how are they being funded?
- Flip-tax administration: If the building has a flip tax (transfer fee), how is it calculated and collected at closing, and who is responsible for it?
- Certificate-of-insurance (COI) process: What are the current insurance and COI requirements for shareholders/owners, contractors, and movers, and who must be named as additional insured?
The Roebling Team
We publish management-company profiles because the managing agent shapes the parts of a transaction a buyer or seller actually feels — how fast a board package moves, what the financials disclose, and how a closing gets scheduled. The Roebling Team at Compass tracks Manhattan's co-op and condo inventory building by building and brings that context to every deal.
Buying or selling in a building managed by Cornerstone Management? Request building-specific guidance →
Corey Cohen, Principal · The Roebling Team at Compass 646.939.7375 · c.cohen@compass.com
Management-company assignments, building policies, contacts and procedures can change. Buyers and sellers should verify current information with the building, managing agent, board materials, and counsel. This page reflects publicly available information and building records on file; The Roebling Team at Compass does not represent Cornerstone Management. © 2026 The Roebling Team at Compass.