By Claire Zulkey

New York Times News Service

For Diana Limongi, the practical benefits of sharing a two-family house in Astoria, Queens, with her parents are manifest. There is access to a car without having to own one, free Spanish immersion for her two children and periodic gifts of homemade lentils left in the refrigerator.

But the best part, the stay-at-home mother says, is when she leaves the house. “I hear my mom talking to my daughter and cracking up. It’s just pure joy, and it’s a beautiful sound. They’re really enjoying each others’ company.”

Multigenerational households — homes where two or more adult generations live together, or those that include both grandparents and grandchildren — are on the rise across the country. A record 64 million Americans live in a multigenerational home, according to a Pew Research Center report, up from 32.2 million in 1950.

There are multiple reasons for this shift: the increasing cost of long-term care; the growing immigrant population, in which shared housing has always been more common; and, of course, rising housing prices. Lawrence Yun, chief economist at the National Association of Realtors, said that multifamily home purchases are especially prevalent now “because home prices are so expensive that the only way to make it work is to double up or triple up.”

John Burns, a California real estate investment consultant, said that he expected the multifamily shopping trend to continue, particularly for anyone born during the 1970s, which he calls “the foreclosure generation.” People in “that group had the highest homeownership ever at their 10th reunion, then the lowest by their 20th,” he said.

And as their parents reach their 70s and 80s and need some help, he said, “you’re seeing those groups pair up in all sorts of ways.”

Finding the right property to meet the needs of multiple generations is an intimidating process, but it can be done — with patience, research, preparation and some luck. For those considering it, here are some lessons from families in which multiple generations live happily together.

Before you look

Be realistic not only about how harmoniously you and your family could live together but also about how happily you could all buy a house together — a stressful endeavor even under the best circumstances. It could mean having some difficult conversations early on and setting ground rules.

Stephanie Jacques Marhue, 37, is a researcher who lives in a converted triplex in Ottawa, Ontario, with her husband, children and parents. They realized early on that her husband and her parents needed to adjust their communication styles. “He’d be like, ‘You need to tell your parents this,’ instead of them talking directly to each other,” she said. “Setting that up straightaway rather than have it being forced — ‘Talk to each other!’ — would have been a big help.”

Now is the time to create a list of property requirements and to be clear on what are absolute must-haves. While looking for a house in Astoria, where she grew up, Limongi, 36, kept in mind her husband’s desire for a yard and her father’s wish for a driveway.

“I had this checklist and was like, ‘We’re never going to find a house like this,’” she said. But they persevered, and in 2011 they found a house, built around 1920, that met their needs.

Limongi was grateful she stuck with the list. “If we had settled for a house that didn’t check all those boxes for both sides, we wouldn’t have been as happy,” she said. “One side would have always felt like they didn’t get what they wanted.”

While house hunting in the Boston area, Melisa Kenslea, her husband and her mother drew up what they called the “house prenup,” a document that addressed how the family would pay for the home and how they would cover expenses. It also included an “exit strategy,” should somebody decide to move out.

“Having that has made everything else much less stressful,” said Kenslea, 33. “We have a document to refer to: ‘This is what we all agreed on: We all signed it.’”

Marhue also advises families to agree on sharing the work of house hunting, as she felt overloaded during the two years it took to find the right property in Ottawa. “I felt like it was my responsibility to find something that fit everybody else. The burden should fall on everybody,” she said. Instead, “everybody kept rejecting what I found.”

And if aging parents are planning on leaving the family home, it is time to start purging now. “We had to push back on that,” said Christa Battaglia, 39, a director of communicationsat Northwestern University who lives in a duplex in the Andersonville area of Chicago with her husband, Brendan Keating, their children and her 83-year-old father. “There’s my dad’s old stuff, his old papers from college. I said, ‘We don’t really need that anymore.’ He’s like, ‘Well, it’s interesting.’”

Jessica Peterson, 37, who works in talent acquisition for an insurance company, said that when she moved her parents from Virginia to Monroe, Connecticut — where she had found a two-family home they could share, so she could help with her ailing father — even a 40-foot U-Haul truck plus another 20-foot truck was not sufficient to transport all their belongings.

Peterson now wishes she had tapped her parents’ network to help with the move. “Don’t be afraid to ask for help but have really specific jobs, like one person to pack the kitchen,” she said.

On the hunt

Once you have decided where you will be looking for a home, it is important to find a broker who knows the area well and is familiar with the multifamily market there. Bear in mind that if the older generation is moving from a longtime family home to a new community, their concerns should be carefully weighed when considering what type of home to buy.

Some house hunters described the in-law suites in homes they saw as “an afterthought” and “mom lives like a troll in the basement,” which is why Peterson’s family would start with the in-law suite during showings. “We knew that if that didn’t fit with what my mom and dad were looking for, it didn’t matter if the rest of the house was beautiful,” she said.

Finding an agent who has experience with multigenerational arrangements can help smooth the process. Karen K.H. Park, for example, specializes in selling multimillion-dollar homes to Chinese and Korean families in the Fort Lee, New Jersey, area. Park, who is Korean-American, said she can commiserate with Asian parents whose children have brought them to the country. “I understand their culture,” she said. Also, “Korean is my mother tongue. I can fully support the family.”

Immigrant families, said Yun of the National Association of Realtors, account for part of the recent boom in the multifamily market, particularly on the West Coast. “There is a larger percentage of Asian and Hispanic families in the region,” he said, “and they are culturally more accustomed to multigenerational living.”

Park said that many of her younger clients looking for a multifamily home prefer a property that is move-in ready, but that is not always realistic when you are looking for something as specific as a home that suits multiple generations.

Mourad Arfaoui, a builder in Queens, has helped renovate houses for multiple generations, including adding extensions, bathrooms and kitchens. His advice: “Stay away from Brooklyn. It’s getting expensive and crowded. You can make a better life on Staten Island.”

Battaglia’s father was initially skeptical about leaving the family home on the West Side of Chicago for a duplex on the North Side, but he changed his mind when he accompanied his grandchildren trick-or-treating. “He saw what a nice atmosphere it is,” Battaglia said. “We took him out to dinner where there are older people. He could more envision himself in the neighborhood.”

Before you sign anything

Depending on the area, multifamily homes can come with tricky regulations on zoning, insurance and taxes. So in addition to finding a contractor to make necessary renovations, it’s a good idea to find a lawyer who can help you figure out any potential zoning issues.

Mark Fishman, 71, and his wife, Pam, 73, bought a four-story brownstone in Park Slope, Brooklyn, in 1981. In 2016, they hired Arfaoui to help convert the house into a two-over-two duplex so their daughter and her family could move in. Since then they have worked with the New York City Department of Buildings to alter their certificate of occupancy to allow a two-family home.

When Drew Zandonella-Stannard, a 34-year-old writer, and her husband, Jacob Conklin, built a cottage in their backyard in Seattle so her parents could live on their property, parking regulations required them to cut the curb and make space for parking in the back. And Peterson, in Connecticut, discovered she would not be allowed to rent her mother’s side of the house whenever she leaves (her father died in early June).

Battaglia said that her father asked a tax lawyer to advise them before they bought a two-family house in Chicago. She and her husband discussed buying the home and renting part of it her father, but they couldn’t afford the mortgage on their own, and her father would have had to pay taxes on any money he gave them to help them with the purchase.

Ultimately, “it was decided that we should just own the property together,” she said. Her father took the money from his house sale and applied it directly to the purchase of the new house. Battaglia and her husband pay a mortgage, while her father does not.

For the long haul

Families who live together happily actively look for ways to make sure that life remains harmonious for all. Anne Luce, 37, an online academic instructional designer in Evanston, Illinois, suggested creating two-year, five-year and 10-year plans.

For example, “What if your family adds another child?” she said. She and her husband had another child while living in a two-family house with her in-laws and young son. “What if one of the older generation ends up requiring significant care?” she said.

She and her husband know that her in-laws have planned well for themselves financially and that there is room in the budget to hire help if needed. “They’ve been really open with us about that, which is reassuring,” she said.

Making sure all parties feel comfortable in their own space can take some doing. Peterson said she was surprised to learn that her parents didn’t feel like full partners. “I always thought of it as it being their side, their property. If they wanted to paint it hot pink, they could, but they didn’t feel like they owned anything.”

It helped to talk it out. “I said, ‘Mom, this is your house. I want you to be comfortable. I appreciate you asking me if you want to rip out a wall, but it’s your house.”