Considering combining apartments in NYC? This comprehensive guide is your essential resource. We break down the entire process, from determining feasibility and navigating the complex co-op board and DOB approval gauntlet, to understanding the real 2025 costs per square foot. Explore design possibilities for horizontal and vertical combinations, and get a realistic project timeline. With 10 interactive tools, this guide helps you plan your dream apartment combination with confidence and avoid common pitfalls.




