Explore this expansive haven nestled in the heart of the Upper East Side an opportunity to enticing to overlook!. This spacious corner unit spans over 2,000 square feet, featuring four bedrooms, three full bathrooms, washer/dryer, and a private balcony with beautiful city and river views. Recently enhanced with elegant hardwood oak flooring, abundant closet space, and contemporary touches, this apartment offers refined living at its finest. Boutique in character, eminently well maintained, and pet friendly, '400' is located in the heart of the Upper East Side. Central Park, Museum Mile, Carl Shurz Park and the East River promenade are in close proximity. John Jay Park is just at the end of 77th Street. Both the new Q and number 6 subways allow rapid access to the rest of Manhattan and commuting, while the Select Bus Service (SBS) is around the corner at 79th Street and will take you quickly to the West Side. The doormen and professional building staff will announce your guests and receive your packages and groceries. There is a brand new renovated "Magic Pass" 24/7 laundry room (Wi-Fi) in the basement. Storage and garage available. (waiting list.) Live in Super. Gifting is allowed. Large (and small) dogs are welcome, cats too! Please note there is a current assessment until the end of December 2027 for $1,028.86 per month