Two summers ago, recent law school graduate Alison Chan was told she needed to quit her full-time job if she wanted to pass the bar exam.

But forgoing an income wasn't an option. In fact, she needed to make more money to pay her monthly expenses: a car payment, rent for her one-bedroom Chicago apartment and food and vet bills for Addy, her adopted papillon chihuahua mix.

Chan, who was already paying other people to walk Addy through pet care platform Rover, realized she could make extra money boarding dogs in her South Loop home while she studied for the bar. She created a profile on the app, and began watching strangers' canines.  

Chan has been caring for dogs for three years now, and made $32,000 on Rover in 2022, according to documents reviewed by CNBC Make It. This year, she's on track to earn an average of $3,750 per month.

Some of that money, about $250 per month, goes toward stocking dog food, treats and beds, but Chan says offering those amenities is part of the reason she's able to charge more than her South Loop competitors.

The side hustle also let Chan keep her full-time job and create another stream of income while studying for the bar. Now, she works full-time as a remote paralegal, uses her Rover earnings to pay her monthly bills and deposits her paychecks from her salaried role directly into her savings account.  

"When I did my taxes last year, I realized [my side hustle] was like a second salary," Chan, 29, tells CNBC Make It.

But her dog-sitting gig didn't become lucrative overnight. Here's how she built a reputation and clientele on Rover, and how she juggles the side hustle with a full-time job.

Setting boundaries

Chan, who grew up around dogs and cats, says it took about a year and a half to figure out a business model. At first, she charged owners about $35 for overnight stays, but quickly realized her prices were lower than nearby competitors.

Most of that money didn't even end up as profit, either. She had to pay out of pocket to cover things like food, dog beds and toys, and Rover takes a 20% service fee from every sitter transaction, according to its site.

She also had to set boundaries — a lesson she learned the hard way. Once, a client's dog chewed through its carrier and relieved itself all over her apartment.

Now, before boarding a new pet for the first time, she asks its owner a series of questions, including: "Is your dog crate trained?"; "Has it ever shown signs of aggression?"; and, "Can it be alone for three hours at a time?"

Establishing a routine

Once the animals are screened, they can freely move around her apartment while she works. Chan clocks up to 40 hours per week dog-sitting, but some of those hours are passive, especially if it's between 9-to-5, she says. The dogs can sleep, play with toys or interact with one another while she's logged on to her paralegal job.

She also has three two-hour drop-off and pick-up windows — one early in the morning, one at lunch and one after work — so her full-time job isn't interrupted by her side hustle. During those breaks, she interacts with the pets and sends their owners updates.

"I didn't realize at that time you can set your own rules and expectations with your clients," she says.

Reigning in the "chaos" has helped her establish a routine, create relationships with clients and raise her prices. So far, it's working. Between 2021 and 2022, Chan nearly doubled her Rover income, and her earnings per month have increased this year, too.

Now, Chan charges about $80 per night and boards up to three dogs — not including 8-year-old Addy — in her apartment. Through Rover, she also walks dogs, lets them out at their own homes and "nannies" them at clients' weddings.

The extra income on a flexible schedule is ideal, but the relationships she's built with the dogs and her clients are why she plans to keep the side hustle running even after she passes the bar, which she's retaking this month.

"I have a steady income coming in, and I would be giving that up when I already have an established clientele," Chan says, adding that both her clients and their pets have started feeling like family.

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