Jared Ebersole knew he wanted an electric skateboard as soon as he saw one. There were just two problems: He was a young teenager, and the one he wanted cost $1,600.

So he decided to make his own, spending $800 from his savings on parts — motors, controllers, remotes and batteries, he says. After roughly half a year of trial and error, including a battery exploding during a test, he built a working board at his parents' home in Catawissa, Pennsylvania. He posted about his success on an online forum, where other users started messaging him, asking if they could buy one from him.

Ebersole made his first sale in 2017, according to documents reviewed by CNBC Make It. By the time he began college at Long Island University in 2020, his company Build Kit Boards was bringing in roughly $300,000 in annual revenue. He used its profits to pay for school, he says: between $4,000 and $6,000 per semester out of pocket, after accounting for multiple scholarships.

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In college, he grew the business further, alongside one employee — who he estimates worked 30 hours per week — and a cadre of friends who helped intermittently during his busy summer seasons. Ebersole himself worked more than 100 hours per week on the business instead of having a traditional college life, and in 2021, Build Kit Boards' annual revenue surpassed $500,000, he says.

"I had very few friends in college; I would literally go to class and not really talk to anybody," says Ebersole, now 24. "I hated my college experience."

He was burnt out, exhausted and on the verge of shutting his business down when his across-the-street neighbor at Build Kit Boards' warehouse — who happened to run an online impact investing community called Impact U, as well as an investment firm — offered to buy a majority share of the business. (Ebersole declined to name the neighbor, citing a confidentiality agreement.)

In 2022, Impact U purchased 55% of Build Kit Boards for $300,000. Ebersole retained a minority stake and withdrew from day-to-day operations, he says. "It was giving me no purpose. I was just doing the same thing over and over again, just at a bigger scale," says Ebersole. "I hit this wall, mentally."

The following year, Ebersole graduated college and put his money from the sale into a new startup venture: He and his friend Luke St. Amand co-founded a startup called Lectec, which sells do-it-yourself electric skateboard kits meant for students.

Ebersole works 80 to 100 hours per week on Lectec, he says — but he's not simultaneously a college student, and he has help this time, he notes. The company currently has two employees in addition to its co-founders, according to its website.

"I'm surrounded by a lot of good people that I can, like, withdraw myself from for even a few minutes at a time," says Ebersole. "Withdrawing myself from the business for a little bit, as much as I can, has been the No. 1 key to avoiding burnout."

Ebersole brought Lectec onto a recent episode of ABC's "Shark Tank," where he said it had brought in roughly $150,000 in lifetime revenue at the time of filming. His pitch landed an investment offer from Robert Herjavec, one of the show's investor judges. Ebersole declined to confirm whether the deal was finalized after filming.

His advice to anyone thinking about building a side hustle: Expect to work hard.

The idea that if you do what you love, you won't work a day in your life, "is the most bulls--- thing ever," Ebersole says. "Find what you love, and you're going to work so hard for that."

Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."

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