Victoria Carroll began doing voiceover work by chance.

The 33-year-old started her career as an actor and, after performing in a play in the Czech Republic in 2015, an audience member asked if she'd audition to voice a character in a video game called "Kingdom Come: Deliverance." Carroll agreed, got the gig, and realized voiceover work might be a good moneymaking avenue.

She's since built a full-time freelance career as a voiceover artist, recording an array of different types of content and working with companies including "Google, Apple, Nike, National Geographic, Adidas, Pepsi, Coke," she says. She finds most of her work through Fiverr, she says, where her gigs start at $30 for 50 words.

She brought in more than $251,000 doing voiceovers in 2023, according to documents reviewed by CNBC Make It. For anyone else keen to make it in a similar career, here's her advice.

Start with 'really low prices and really long hours'

Carroll recommends putting in long hours and keeping prices minimal at first.

She created her Fiverr profile in 2018 "and didn't say no to any work at the start," she says. "And I was working sometimes literally 18-hour days and working seven days a week." It was hard, but she stands by that level of dedication to building her businesses and client base.

She also kept her prices low to attract customers — sometimes she even did work for free to build up her portfolio. She's in touch with other successful Fiverr freelancers "and we all started the same way," she says, "really low prices and really long hours."

'Deliver really good work'

Carroll also advises making sure your customer service is top notch.

"You want to respond to client requests really quickly," she says. "You want to deliver really good work." She always makes sure she understands exactly what the customer wants, delivers high-quality voiceovers and fixes anything they're unhappy with.

Generally speaking, Carroll will only do one free revision. After that, she'll charge for changes. The policy has "saved me a lot of strife," she says. Still, if a client is willing to pay, she's happy to keep tweaking. She recently worked with someone who asked for six revisions altogether.

Delivering high quality work and agreeing to revisions ensures your clients feel good about the product. Plus, especially on a freelance marketplace like Fiverr, "it's really important that you get good reviews," she says, adding that that "lets the Fiverr algorithm know that you are a quality seller and helps promote you more."

'99.9% of the voiceover actors I know record in a closet'

Finally, Carroll recommends investing in good tech.

"You have to have a pretty good quality mic" to create those recordings, she says. She started out with a snowball mic, which these days goes for about $50. She then upgraded to a Shure SM7, which can go for about $400.

You'll also want a quiet place to record. "99.9% of the voiceover actors I know record in a closet," she says. "It's small, it's quiet. Clothing is a really good buffer for sound." Some people add extra sound paneling as well. Carroll, who lives in Los Angeles, records in her closet or a home studio.

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