McMahon says one of the challenges of being a teenage entrepreneur is always needing to exceed expectations.
Building trust is especially important to get people over any misgivings they may have about using the services of someone so young.
But it also creates opportunities, she says. "People are always wanting to help me because of my age.
"For example, I'm going to photograph the wedding of a woman from New York who exhibited in an art gallery when she was 9. She had great connections from that experience and wanted to help me because someone had helped her follow something she loved."
Oliviah Theyers-Collins is programme manager at Venture Up, a six-week accelerator programme for entrepreneurs aged 17-21, which will have its next intake in January.
Theyers-Collins believes entrepreneurship is increasingly being embraced by young people as a career option, thanks to factors such as the Young Enterprise Scheme that runs in high schools and tertiary institutions offering clubs, competitions and courses.
"It is also a by-product of this generation where they have access to so much through globalisation and the internet," says Theyers-Collins.
"Parenting styles have changed, too, so young people are more empowered to think and do things for themselves, and take more risks."
Twenty-year-old Jamie Beaton co-founded Crimson Consulting in his teens. It has 22 fulltime staff and 450 contractors and offices in Auckland and Sydney.
Beaton is also studying applied maths at Harvard and is a passionate exponent of entrepreneurship, which he says offers a platform to make an impact on a large scale.
"The platform I have with this business to generate change and rekindle how people think about education is the most exciting aspect for me," says Beaton.
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