A little over six years ago, Joel Young found himself in a situation many American families are facing: He was deeply in debt with an unpredictable job and young children to provide for.

As a pastor, Young's income "was all over the place," he says, and so were the gigs — he was constantly moving his family to a different town or state with every new church. Young and his wife Jenna, both now 35, remember brainstorming ways to pay off the $50,000 they owed thanks to expenses like credit cards, car and personal loans and medical bills.

So when Young hired a voice-over actor to help with a church project for $10 on Fiverr — the online freelance marketplace that launched its IPO on Thursday — it sparked an idea: Why not try selling voice-over work, himself? It seemed simple enough.

He and his wife, Jenna, "kind of had this little, quick conversation, and I said 'Well, the truth is I have all the equipment I need.' I had a leftover microphone from a band I was in, I had a MacBook, and that's pretty much all you need to do that," Young tells CNBC Make It.

After just 18 months of offering voice-over services on Fiverr, Young paid off the family's debt, and now, since selling his first service in February 2013, Young has made more than $1.5 million in income on the platform.

"To be honest, it's kind of snuck up on me," says Young of the million-dollar benchmark.

From side hustle to only hustle

Originally, Young wasn't sure his idea for a side gig would pan out.

He has a background in public speaking and "was the kid that was always talking growing up," he says. "But I had zero experience in voice work, so I thought, who knows if this will even work?" Young adds.

He figured he might pull in an extra $40 or $50 a month, charging $5 at a time for services like reading scripts for commercials or doing narration for audio books.

The first month, he made $400.

The Youngs "were both just kind of blown away by what we had earned just in a couple hours a night, when I got home from my regular 9 to 5, just on the side," he recalls.

And after Young paid off his debt, an idea began to take shape: What if this was his main gig?

"We kind of set some preliminary goals where we said, 'Well, if we can get the monthly income to this, maybe we could start thinking about moving on to this as a full-time job,'" Young says.

Getting there wasn't easy, he remembers. He was working on his Fiverr services after his day job, sometimes until 1 or 2 a.m.

He also expanded his services to include animated explainer videos after clients who purchased his voice-over work wanted video content as well. He taught himself to do the videos and "learned on the job, basically" he says. As with the voice-overs, he charged almost nothing until he honed his skill.

Within six months of setting his goals, he was pretty close to matching the income he received as a pastor.

"We made a plan, we made sure it was smart, we saved up a little emergency fund, and eventually when those paychecks kind of equaled each other, we decide we were close enough to make the jump and I left my full time job as a pastor and started doing this side hustle thing full-time as my work" in 2015, Young says.

Today, Young's Fiverr profile shows voice-over services including a "radio quality" voice-over, priced at $5 per 50 words with a minimum order requirement of $30. For videos, his rates are between $350 to $750 for 30 to 90 seconds, but routinely has projects that creep into the thousands. The average customer, he says, spends more than $500, and he typically creates over 50 videos a month. He's done work for big companies like Comcast, Lowe's, Home Depot, State Farm and even the U.S. Navy, as well as colleges and universities.

Young does have his own website, which he operated before he started offering his services on Fiverr, but he tells CNBC Make It that his overall income is split about "50-50" between his own website and Fiverr, and he's made roughly $1.5 million in total from the freelancer platform.

"Because I've maintained good reviews over the years and have increased the quality of my services, the marketplace brings the clients to me [through] algorithms they've developed to connect quality buyers and quality sellers," Young explains. "Over the years, however, many of the clients the marketplace has connected me with have become returning customers. I would say that 40 to 50 percent of my clients will come back if they viewed their first project with me as a successful one."

Lucrative in more ways than one

Despite Young's financial success, he says it wasn't the money that drove his determination to build his side hustle into a full-fledged business.

"It was honestly only just the stability and the freedom that I concentrated on," Young says. "It was about what this way of life meant to my family, what the freedom would enable us to do."

The financial freedom that came with being debt-free allowed the Youngs to adopt their third child, now a 5-year-old boy, about two years ago. (Their other two sons are 9 and 11.) And it even enabled them to live in an RV full time for roughly three years — they traveled the country, showing their kids as much of the world as possible. Recently, though, the family bought a house and settled down in Boulder, Colorado, where Young says he serves "at a very high level at my local church every week."

"I love that I'm able to give my time without having to be on the church payroll as a staff person," he says. While he still works a lot, Young says his online career gives him the flexibility to still spend a lot of time traveling with his family and "work sporadically throughout the day so we can mix in some fun times in whatever city we're in," he says. Jenna is a full-time mom.

"It's never been about money for us…" Young reiterates. "But it is kind of neat to look up and see. That is an amount of money that would have taken me decades to earn without this platform."

How to turn your hustle into a full-time gig

Through his experience, Young has learned a thing or two about what it takes to be a successful online entrepreneur. If you're eager to get started, one thing Young emphasizes is not underestimating the skills you already have.

"I've heard other people talk about this thing called the curse of knowledge," he explains. "That's when you understand something, or when you know something and grasp it, you're cursed in the sense that you believe everybody understands that."

You likely already know how to do something that provides value to someone else. It's about recognizing that skill as valuable, which can be hard to do.

"I did the same thing when I started," Young says. "I was offering something that I thought was easy. I'm talking into a microphone — that's stupid, who would pay for that?"

Thousands of people, as it turns out. "Because no one wants to do it, no one's good at it, no one can do it," he says. "But because I've always been able to talk and I've always been good at it, I thought, 'Well this is easy, I'm just talking.' It's that curse of ability."

Young recommends getting an outsider's perspective on what your natural abilities are. Ask a friend or co-worker to list three things you're good at that most people aren't. It can shed light on what you could potentially make money from.

Another important attribute, says Young, is being adaptable and being able to pick up and learn things quickly.

"What I've learned in my business is that the skills I'm learning today, I didn't have five years ago and I didn't even know I needed two years ago," he says.

With the availability of YouTube and Google, there's "nothing you can't learn on the internet," Young says. "From fixing your car to writing software and code, to learning a musical instrument. And if you don't master the skill of teaching yourself new things, you'll be left behind."

Even if you feel like your skill set isn't as sharp as you'd like, don't let that sway you.

"In the early days, when my work was not as great, I was serving a different client base, I was adding value to them because my prices were so much cheaper. I was adding value to them at the level I could," Young says. " Now, I'm adding different value at a different level. But the reality is, if I hadn't started at the first step, I wouldn't have gotten to the step I'm on today.

"Don't think you have to get to the ideal level before you start," he adds. "Because that's how people end up sedentary, wasting their whole life doing something they hate, because they never started when they never tried."

Finally, keep your eyes open to trends and what's happening in your marketplace, advises Young, and listen to what your customers want. It's why Young started offering his lucrative explainer videos.

"I'm a huge believer in standing on your own two feet and making things happen for yourself," says Young, and he hopes his kids will learn from his example. "I can only assume my children will inherit that desire for freedom and sense of entrepreneurship...if for no other reason than we have been blessed to enjoy a great life because of my business."

Disclosure: Comcast owns NBCUniversal, the parent company of CNBC. This article was originally published on June 19, 2018 and was updated on July 26, 2018 and June 13, 2019.

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