Chinatown (big tenement, maybe 25+ apts): (To me) Enough to smile and say hello, (To my husband) depending on who, either chit chat at the mail box or give the very serious evil eye.
LIC (old 3-story building): Everyone knew everyone's business. I loved the location, not my neighbors. First floor - Neighbor #1 didn't know. Moved out. Couple moved in. They wanted to be very neighborly, were very gung ho, invited us to hang out a few times, but never did. Then I soon moved. Neighbor #2 had lived there 30+ years. I don't think he had paid rent in at least 10. At first he was really friendly and actually had to avoid him sometimes because he'd talk forever, and he invited me in for a tour of his apt., invited to a couple parties. BUT then after a year or so he turned...crazy and angry...like he was off his meds and would bang on our door accusing us of spying on him. Floor 2, Neighbor #3 horrible, alcoholic, creepy super, who harassed tenets and everyone avoided. He had lived there 30+ years. Neighbor #4 - I hung out with a couple times, had a lot of building gossip, lived there 5+ years. Then suddenly disappeared overnight. 3rd Floor, Neighbor #5 - Never really figured out who lived there, when. Or if anyone actually lived there. It was rented by a business man for his mistress. Or mistresses. Best neighbor ever.
Lower East Side (old but nice building, 100 apts give or take): A lot of the people were very nice, smiled, say hello, chitchat at the mail box. I didn't know my immediate neighbors that well, but they were very nice and if I really needed something I knew I could knock on their door.
Chinatown (small tenement, maybe 12 apts): (Me) I met my immediate neighbor, she only spoke Mandarin and I only speak English. But she seemed nice. Her daughter was there once and I spoke with her and apparently I was the first English-speaking neighbor ever who introduced myself. She had lived there for 30-40 years. (My husband) Would chitchat with a neighbor on a regular basis, seemed like we would have been friends with them him if we lived there longer.