You’ve probably heard of people who own property purely to rent it out. Usually, the owner or owners live elsewhere. Well, one couple with digs in Jersey City is doing things a little differently.

Jennifer Liepen, 32, and Sandy Patch, 33, own a $345,000, four-bedroom house in New Jersey, but spend most of their time living a nomadic lifestyle across the Hudson River, they told the New York Post. Meanwhile, the house’s rooms are being rented on Airbnb for $60 a night, with one guest staying for free, in exchange for helping with upkeep.

Liepen and Patch are pet sitters, charging $30 a night for one dog or cat, and $5 more per additional pet, and they’re sleeping at their clients’ homes. They started their company, Woof Woof, in 2015.

This contributes to their weekly budget of $100. Their expenses include about $200 a year for Citi Bike memberships, $20 a month for Movie Pass memberships, $75 a month for a four-by-four-foot storage unit in Chelsea, and $75 a week for groceries. They sometimes spend even less on that because they often eat out of restaurants’ garbage cans.

They only pet sit a total of a few weeks each year. So, they spend the rest of the time traveling light and crashing at the homes of friends and family members.

“It’s a sustainable process that lets us pay the mortgage,” Liepen told the Post.

They expect to make a profit once they pay that off, in about 15 years.