It's still a small budget - each series is six episodes, and each episode is eight to 10 minutes - but these young women are so persuasive and talented that Flat3 has proved to be a minor internet phenomenon.
They've been invited to festivals in Melbourne, London and New York, and the United States seems to be their biggest fan base outside of New Zealand - Fong was even recognised on the streets of San Francisco earlier this year for her role.
The slightly absurdist, everyday situational plot lines have clearly struck a chord with audiences all over, as the trio deal with work or lack of it, love, etiquette, cultural barriers, and prejudices with a light, self-effacing touch.
The third series guest cast includes Madeleine Sami, Kimberley Crossman, Olivia Tennet and Pua Magasiva (who may or may not be shirtless), and its surprisingly fresh take on young adulthood in New Zealand has made it a welcome addition to the independent web-comedy world, and to local culture.
"We just wanted to work together and make something," Fong explains about their initial drive. "We wanted to do comedy."
Adds Lau: "Three girls, all of us are Asian obviously, and that in itself was enough for us to be able to go, 'Yeah, we don't know anyone else making that'."
Then they approached Liang for some advice and found she was keen to get involved, so brought her on as writer/director and co-producer.
The notion of a web series was their next brainwave.
Watch the first episode of Flat3:
App users: Tap here to view video
"You can't just create something and then take it to a production company and hope they'll put it on TV; it doesn't work like that," says Lau.
"But between us we knew we had friends who could help us film, and Roseanne could edit, and we'd all sit together and storyboard. So we knew we had the tools and skills between us to bring a web series together."
Auckland Daze provided some early inspiration, as did hit American web series Awkward Black Girl.
"Awkward Black Girl was the first web series that we really seized on, and watched with the intention of making our own," Liang explains.
"We looked at its style, the use of narration, voiceover, do they speak to camera? Is it interview style? We worked out what could work for us."
More recent web series High Maintenance and Broad City (which has now been made into an HBO series) have also provided inspiration - not in content or themes, but simply in the art of creating a perfect bite-sized episode.
One thematic comparison that does turn up frequently is Girls - also being about a bunch of young female friends/flatmates bumbling through life in the city, and the foursome are proud of the references.
"It had just started when we were creating Flat3, and we were certainly inspired by it. We definitely take it as a compliment."
There's a shared aspect of revelling in everyday awkwardness and a certain openness that creates great comedy. And of course there are moments of vulnerability and pathos, and sadness - it's all based on real experiences after all.
Watch episode two of Flat3:
App users: Tap here to view the video
"Unfortunately, yes, the storylines are often taken from our own lives," laughs Fong.
"Everyone throws ideas in and then we stretch them. Season three is a bit different, a bit wider, but season one and two were very much our own experiences, along with stories we've been told by friends. The mistaken prostitute episode in season one, that was actually based on Roseanne's own experience."
"And the whole storyline where the guy in the band breaks up with Lee, and he's really passive aggressive about it - that happened to my flatmate," says Lau. "It's pretty much verbatim. She was totally happy for us to use it in the show."
So the characters are drawn from the real-life world of Fong, Lau and Xue, but it's worth pointing out that they are still exaggerated characters - it's not reality TV.
"I'm not a slutty bitch. Just to confirm," Fong laughs.
"Yes. Jess is really hard working, and does not get naked that much," confirms Liang.
The interview is peppered with laughter and quick quips - there's clearly natural chemistry between the group, and that's what makes the show such an independent gem.
Who: JJ Fong, Perlina Lau, Ally Xue, and Roseanne Liang
What: Kiwi web series Flat3
Where and when: A new episode goes online each Friday, and all three series can be watched at www.flat3webseries.com.
