We were kindly welcomed by Nick on the day we arrived, and the apartment itself perfectly suits 2. The two hosts (Nick at least) were easy to live with and didn't mind when we got home later in the evenings.
The overall value for money of the apartment is amazing, considering the level of comfort as well as the proximity to the city center and Central Park. It takes about 15 minutes by metro to get to Grand Central Terminal as well as 5 minutes on foot to Central Park. Stay with Nick and Maria if you can, they'll make it worth your while.