In 2020, Vionna Wai, 30, and her husband, Chucky Hui, 29, moved into a two-family home in Bensonhurst, Brooklyn, with his parents.

The total monthly rent for the 1,792-square-feet house is $3,500.The couple pays $1,600 a month to live in the one-bedroom, one-bath apartment on the second floor, while Wai's in-laws pay $1,900 and live on the first floor, according to documents reviewed by CNBC Make It.

Together the family paid a $3,380 security deposit upfront.

Wai and Hui live in an area that she calls "the suburbs of Brooklyn." Bensonhurst is deeper into the borough and more residential compared to neighborhoods like Williamsburg or Greenpoint which are trendier and closer to Manhattan.

"I like living here because it's close to my family. I like being in a suburb environment but also having the benefits and access of being in the city," Wai says.

The location also affords the couple and their in-laws below-average rent costs. The average size for a Brooklyn, N.Y., apartment is 660 square feet and average monthly rent is $3,558 a month, according to RentCafe.

The couple also enjoys the added bonus of home-cooked meals from Hui's dad.

"I was scared to live with my in-laws because we weren't married at that point," Wai says. "There's definitely a lot of benefits living with my in-laws. We just kind of go down and eat dinner."

In addition to splitting rent, the couple share the $80 monthly Wi-Fi bill with Hui's parents, too.

While their living arrangement might be familiar to some — 16% of U.S. millennials lived with their parents in 2022, according to Axios — what sets Wai, a construction engineer, and Hui, a UX designer, apart are the 150 houseplants and two cats, Mi and Ding, they moved in with.

"When I look at my houseplants, I really am living in the moment. I don't think about like my stress or worries about work or anything like that," Wai tells CNBC Make It. "I'm just focusing on taking care of my plants and making sure they're happy and that for me is very calming."

Wai's plant collection might be overwhelming for some, but she doesn't think 150 plants is excessive.

"I'm just a homebody that wants to stay at home all day to play with my cats and plants," Wai says. "Once I go to work, it's all fast-paced... but when I come home, it's a complete switch. I'm in my own element and everything's just very calming and lively."

Wai says there is actually very little maintenance — she spends about 30 minutes a week watering them and does some pest control between seasons.

"They just need water, sun, and some love," Wai says. "It's really not that hard to take care of them but I think people fail to see them as living things sometimes. How much love you put into that plant it'll give back to you."

One of the most expensive plants in Wai's collection is a Phildendrom Florida Beauty she bought for $350 during the pandemic. Wai and her friend split the cost with the plan of propagating the plant. While the price tag might have scared some away, Wai says it was 100% worth it.

"It gave me so much joy."

Though Wai admits she was scared it would die on her: "Part of the journey is nursing it back to health and being able to share with friends."

Because many plants can be toxic to cats, the couple has an area they call "the cat jungle corner" that houses their pet-friendly plants. Mi is 10, while Ding is five.

"I've learned to train my cats to coexist with my plants," Wai says.

The couple also makes sure to use cat repellant on the plants and keeps the toxic ones out of Mi and Ding's reach.

The only place that Wai and her husband don't have any plants at all is in their bedroom.

Because the couple is currently renting, they made sure to keep their plant set up renter-friendly but eventually, Wai admits that she would love to have a greenhouse.

"I always have this dream of moving to Japan and just living in the countryside with the rice paddies on the side and just, you know, a greenhouse and just have that calm, like country life," she says.

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