How can people possibly afford to live in one of the most expensive cities on the planet? It’s a question New Yorkers hear a lot, often delivered with a mix of awe, pity and confusion.

We surveyed hundreds of New Yorkers about how they spend, splurge and save. We found that many people — rich, poor or somewhere in between — live life as a series of small calculations that add up to one big question: What makes living in New York worth it?

Rent is not the largest monthly expense for Anala Gossai and Brendon O’Leary, a couple who live on the Upper West Side of Manhattan. That would be child care.

They spend $4,200 each month on day care for their 1-year-old son, Zeno.

“We really liked the center,” Ms. Gossai, 37, said. “Neighbors in our building love it. It’s actually pretty middle of the road for cost. Some were even more expensive.”

The rent for their one-bedroom apartment is $3,900 per month. Space is tight, but the location is priceless.

“We’re right across from Central Park,” she said. “We can walk to the subway and the American Museum of Natural History.”

‘Middle Class’ in Manhattan

Ms. Gossai, a data scientist, and her husband, 38, a software engineer, met in graduate school. Their household income is roughly $500,000 per year. While they make a good living, they try to be frugal and are saving money to buy an apartment.

They moved into their roughly 800-square-foot rental eight years ago when it was just them and their dog, Peabody, a Maltese poodle. Now their son’s crib is steps away from their bed. They installed a curtain between the bed and the crib to keep the light out.

Like many couples, they have discussed leaving the city.

“When we talk about the possibility of moving to the suburbs, we both really dread it,” Mr. O’Leary said. “I don’t like to drive. Anala doesn’t drive. I feel like we’d be stuck. We really value being able to walk everywhere.”

Ms. Gossai is from Toronto, and Mr. O’Leary is from Massachusetts. In New York City, wealth is often viewed in relation to your neighbors, and many of theirs make more money. The Upper West Side has the sixth-highest median income of any neighborhood in the city, according to the N.Y.U. Furman Center.

“I think we’re middle class for this area,” Mr. O’Leary said. “We’re doing OK.”

The couple tries to save about $10,000 each month to put toward an apartment or for an emergency. They prioritize memberships to the Central Park Zoo at $160 per year and the American Museum of Natural History at $180 per year.

Their son likes the museum’s butterflies exhibit and the “Invisible Worlds” light show, which Mr. O’Leary said felt like a “baby rave.”

Ordering Diapers Online

The cost of having a young child is their top expense. But they hope that relief is on the horizon and that Zeno can attend a free prekindergarten program when he turns 4.

For now, they rely on online shopping for all sorts of baby supplies. The family spent roughly $9,000 on purchases over the last year, including formula and diapers. That included about $730 for toys and games.

Ms. Gossai said one of her favorite purchases was a pack of hundreds of cheap stickers.

“They are good bribes to get him into his stroller,” she said. “Six dollars for stickers was extremely worth it.”

They splurge on some items like drop-off laundry service, which costs about $150 a month. It feels like a luxury instead of doing it themselves in the basement.

Keeping track of baby socks “completely broke my mind,” Ms. Gossai said.

Their grocery bills are about $900 per month, mostly spent at Trader Joe’s and Fairway. Mr. O’Leary is in charge of cooking and tries to make dinner at home twice a week.

They spend about $500 per month on eating out and food delivery. A favorite is Jacob’s Pickles, a comfort food restaurant where they order the meatloaf and potatoes.

Saving on Vacations and Transportation

Before Zeno, the couple spent thousands of dollars on vacations to Switzerland and Oregon. Now, trips are mainly to visit family.

Mr. O’Leary takes the subway to work at an entertainment company. Ms. Gossai mostly works from home for a health care company. They rarely spend money on taxis or car services.

“I’ll only take an Uber when I’m going to LaGuardia Airport,” Mr. O’Leary said.

Care for their dog is about $370 per month, including doggie day care, grooming and veterinarian costs. Peabody is getting older and the basket under the family’s stroller doubles as a shuttle for him.

They love their neighborhood and the community of new parents they have met. Still, they dream of having a second bedroom for their son and a second bathroom.

Their kitchen is cramped with no sunlight. So they put a grow light and plants above the refrigerator to brighten the room.

Since they share a room with their son, he often wakes them up around 5 a.m.

“In the sweetest and most adorable way,” Ms. Gossai said.