A young woman spent the night with Rob Curtin at his apartment in Astoria, Queens, some while back, and a good time was had by all.

Mr. Curtin’s landlady, who lived in the ground-floor unit of the two-family house, made no secret of her disapproval.

“She said: ‘You shouldn’t be partying with girls this late. Girls like that are no good,’ ” recalled Mr. Curtin, 33, who works in television production. “She was very interested in my love life.”

The landlady’s assessments of those friends, while not necessarily or consistently off the mark, were disconcerting, said Mr. Curtin, who had previously — and happily — lived in a landlord-occupied building. There, the owners had given him espresso, not advice.

“It was awkward that she was making comments at all,” he said. “But I wanted the relationship to be good while I was living there. She meant well, but really, it was none of her business.

“But,” he added, “maybe it was her business, because I was living in her building.”

For the majority of those who rent apartments in New York City, the landlord is simply the person to whom they make out a monthly check, a faceless being who races to the bank with that check — but doesn’t always respond with similar speed when there’s a problem with the boiler.

For some, however, the landlord is not abstract. For better (he’s always around checking up on things) or worse (he’s always around checking up on things), the landlord is the upstairs or downstairs neighbor. It’s the durable stuff of movies and sitcoms, like the 1960s series “Hey, Landlord” and the ’70s series “Three’s Company.”

Life with the landlord has its own particular complications and compensations. These range from the too-much-in-your-face and too-much-in-your-business sort, to the homeowner whose table always has an extra place. If the relationship is contentious— well, you know where the door is. But if it’s harmonious, that could translate into attractive terms when the lease comes up for renewal.

There are no hard figures on how many New York City apartment buildings have an in-house landlord. But it’s more likely to be the arrangement in small buildings, more likely on side streets than avenues, and more likely in the outer boroughs than Manhattan. That’s “because the housing stock, a lot of duplexes, is built for it,” said Jonathan J. Miller, the president of the real estate appraisal firm Miller Samuel.

“Having the landlord in the building is more common than you think,” he added. “But it isn’t something you see in the marketing or listing of a building, and it’s not seen as an amenity like a gym or a roof deck that will affect the rent you pay.”

There can be advantages to having a live-in landlord. “The assumption is that things will get fixed quicker because the landlord is there,” Mr. Miller said. “He’s subject to the same inconveniences as the tenants, so if the hot water is off, he has an incentive to fix it.

“By the same token, you may have to be more mindful of your behavior than in a large building where the landlord lives elsewhere.”

Sunny Zachi, the owner of Alpha Properties, a rental agency in Manhattan, says he makes a point of outlining the virtues and drawbacks of living in a landlord-occupied building. “I tell a prospective tenant that the building is clean and well taken care of. But then I say, ‘Guys, the landlord lives there, so there are things you have to be cautious about; he doesn’t want people who have parties until 4 a.m.’ ”

Landlords and tenants have to find a balance between privacy and intimacy that suits everyone.

The women who cycle in and out of the three-bedroom second-floor apartment that Melanie Adsit rents out in Astoria are tenants, but often they also become friends.

“We actually hang out and have dinner parties,” said Ms. Adsit, 37, an art education consultant who lives on the first floor with her husband, Alex Eaton, 36, a freelance cinematographer for film and television, and their newborn daughter. And sometimes, tenants become family. Ms. Adsit’s brother married a woman who had lived upstairs.

“I feel our tenants have been very patient with us,” Ms. Adsit said. “They know they have a good deal, so they’re not demanding.”

Megan McDonell, one of Ms. Adsit’s tenants, says that good deal includes the backyard. “Melanie and Alex are like, ‘Go on out there and invite your friends over,’ ” said Ms. McDonell, 31, an editor at a publishing company. “During Hurricane Sandy both my roommates were stranded elsewhere, so Mel and Alex invited me down to dinner and to hang out with them.”

Despite the general coziness, Ms. Adsit said there had been some minor annoyances in the past, like the sound of clicking high heels overhead, and an oversharing tenant. “If you said ‘How are you?’ ” she recalled, “you’d get an epic tirade about the latest terrible things that were happening in her life. We used to watch from the window to make sure she was in the apartment before we went out, because we didn’t want to be stuck on the stoop for 20 minutes listening to her problems.”

Peter Harris was naïve, he said, to think it didn’t matter that the landlady lived on the premises when he and his wife, Jan, rented a duplex apartment on the Upper East Side in the late 1980s and early ’90s. “Then we found out she was a combination of nosy sitcom neighbor and cuddly grandma,” said Mr. Harris, 69, an executive in the private equity business and the former chief executive of F.A.O. Schwarz and the San Francisco 49ers football team.

“She would not just note who came and went; she had a point of view about their demeanor. And when she came to our door, it was almost like a military inspection as she looked over my shoulder to see how clean our apartment was.”

The landlady’s probing went further, according to Mr. Harris. “She became very interested in our lives, including our latest in-vitro success. She wanted to know the details in a way that made it seem as if she were the third person in bed with us.”

And sometimes, he added, there were expectations that they would be there for her. “She asked us to feed her cat and accept deliveries when she wasn’t there,” Mr. Harris said. Once, in a swap of landlord-tenant roles, she even asked him to come look at her backed-up sink.

For a 36-year-old freelance medical writer living in a two-family house in Queens, the elderly landlady seems to be a combination of grandma and Santa Claus, “because she knows when you are sleeping, she knows when you’re awake.”

The writer, who asked that her name not be used because she hopes to renew her lease, said she thought the landlady was a very sweet person. “I like her,” she said. “I really do like her.”

But when she and her husband moved in last February, the lack of a door on their baby’s bedroom generated a battle, with the landlady finally saying to them: “Why do you want a door? Oh, you don’t want to hear the baby cry?” It felt like “a commentary on our lives,” the writer said.

With the demands of work and child care, the couple didn’t have time to buy curtains, and as a temporary solution, put cardboard boxes over the glass to keep the light out. “The landlady said the boxes didn’t look good and she gave us curtains,” the writer said. “I didn’t like them, but I put them up. If I hadn’t, I think she would have been hurt. It was like she was giving us a gift.”

It has taken a year for the couple to make their peace with the situation, to accept the trade-offs: the lack of privacy weighed against the attractive rent. The landlady’s reproving comments that the baby isn’t dressed warmly enough weighed against the freshly renovated apartment. The monitoring of their comings and goings weighed against the lovely view of the Manhattan Bridge and — what with no one above them or next door — the peace and quiet.

The writer is also aware that the living arrangements present challenges not just for her, but for the landlady as well.

“We’re paying tenants and we have our rights,” she said. “But I want to be respectful of the fact that this is my landlady’s home. I can tell she struggles with having someone live here.”

There is no such struggle for Dorothy Lashley, who has owned a brownstone in Harlem for 30 years. She lives on the first and second floor and rents out the third and fourth to tenants who call her Mama.

“It’s been a pleasurable situation so far,” she said. Perhaps that’s because Ms. Lashley, 71, spells out the rules of engagement before a lease gets signed. “We don’t slam doors,” she said. “If you want to have a party, invite everyone. People don’t have to come, but they have to be invited. If you don’t fit in, you have to move out.”

“Dorothy makes it homey,” said Barbara Morris, 64, a retired nurse who has been a tenant of Ms. Lashley’s since 1998. “People don’t have to worry about heat. If you need something done, it’s done right away.

“Last week I cooked some greens and rice in chicken broth and took a plate down to her,” added Ms. Morris, who was recently invited to Ms. Lashley’s apartment for a birthday dinner of lasagna and cake.

Mr. Curtin, meanwhile, weary of the incursions on his privacy, moved out as soon as his lease was up, and has since bought a condo in Long Island City. “My building is friendly but impersonal,” he said, sounding relieved. “I’d probably have to be dead for a few days before someone would come and check on me.”