Australian kitsch-pop band Client Liaison’s lead singer Monte Morgan is unloading one of 50 suitcases of clothing from a van outside his rental in Sydney’s Redfern when I arrive. He’s wearing a pink vintage shirt and lilac slacks.

Rest comes at a premium for Melbourne’s Monte Morgan and Harvey Miller, who’ve taken what began as a musical love letter to daggy kitsch and rapidly blown it out to become one of Australia’s biggest bands and, now, a fast-evolving, multidisciplinary branded universe.

This time it’s fashion that has brought Client Liaison to Sydney. They’ve hired two houses, side by side, in a mad scramble to prepare for their first-ever Fashion Week show and afterparty.

The house is a hive of activity. Yesterday the Melbourne band launched a new single (Survival in the City) and as we wrap our interview they’ll announce their own national festival, slated to attract more than 30,000 people, before rushing off to a fitting. In the next room, people are running around looking for the best wi-fi signal amidst stacked cases of gear, get-ups and God knows what else.

“Collaboration has always been huge for us,” says Morgan. “Once people get onto the [Client Liaison] philosophy and the world, they can start bringing in ideas that can often be superior to ours. It always ends with us, but everyone has different fortes,” says Morgan.

Why a foray into fashion? “I don’t mean this as a jab at the Australian fashion community, but if we’re not going to traverse the space between music and fashion and put on events, who’s going to fucking do it?” says Miller.

Spanning a full menswear, womenswear and accessories range, Client Liaison Deluxe Line is perhaps the band’s most ambitious voyage into brand territory yet. It’s taken them a year to perfect, and cost them a pretty penny, too.

“When you’re 18 years old, there’s nothing other than sport that commands your life [like] music and fashion. They are the biggest things in terms of influence in pop culture,” says Miller, who once worked at Melburnian street-style institution FAT.

“We’re constantly reinvesting. We’re always trying to be bigger and greater, and expanding our team,” says Miller. “But music and fashion have always gone hand in hand, so when the opportunity came to do another range of clothing, we wanted to take it to the next level,” says Morgan. “We’re hoping they can market each other, too. There’s no one in fashion week that’s also being mentioned on radio. And there’s nobody played on radio that’s also in the fashion press.”

Visuals will be front and centre at the off-site show at Sydney’s Overseas Passenger Terminal tomorrow. The pair remains tight-lipped on the specifics, but do let on that they’ll perform as part of the show, models will arrive in lifts, and the smell of wattle and gumnuts will waft throughout. Standard fare, really.

The Client Liaison brand works overtime in pretty much every medium imaginable, from music videos to live shows, outfits to outfitting, and social content to brand partnerships. During our conversation, Miller alternately refers to the band as an agency, an enterprise and a media channel. “Our goals for this year are fashion and Europe,” says Morgan.

While most acts use touring and sales revenue to buy better gear, Morgan and Miller typically spend their money on suits and smoke machines. Their appreciation for aesthetics has served them well as a brand coming of age in the Instagram generation, and now as a fashion label. “The visuals are so important. People see before they look and they’re flowing through so many images they don’t even have time to stop for the audio. It’s only when they see a live act. So it’s silly not to,” says Morgan.

Fashion would be a strange thing to take on if Morgan and Miller hadn’t already been clothing-obsessed for years. They clearly know how to get it done; their first leisure collection sold out nationwide and was picked up by Urban Outfitters in Europe. Client Liaison Deluxe Line ramps up the ridiculous; it features overly printed suits, Sheraton Mirage-inspired sweaters and outback-coloured eyewear. Every detail has been fanatically fussed over by the band and their expanded fashion team, from fabrics to the cuts and the weight of each piece.

“I think about some of my favourite brands, like Versace, Tommy Hilfiger and Calvin Klein. The narrative and history behind them is really significant,” says Miller. “You look at Calvin Klein’s advertising in the ’90s and it’s just such a strong world. I would hope that we could create a similar world for people.”

“We’ve always collected vintage clothes and then whenever I’d go overseas I’d go to tailors and get clothes made … suits and that sort of thing,” says Morgan. “So when we started touring Asia we’d spend weeks there just getting fitted, trying to organise another gig to get back there, source fabrics, get more fittings and more suits.”

As far as the boys are concerned, any distinction between commerce and creativity is purely arbitrary if you do it well. They’ve featured everyone from Foster’s to Ansett in their video clips, and actively pitch themselves to former cultural monoliths such as Pepsi. “When we were starting out and did tour posters, we always put fake logos at the bottom,” says Monte, laughing. “You know, Jim’s Mowing. But now we’re actually approaching them and saying ‘Hey, let’s do a mowing exhibition.”

And they won’t stop there. “We just had the most horrendous lunch in Circular Quay and we said to each other, we have to create “Cafe Liaison”. It’s going to be based off the ’90s, with large focaccias and screech-and-cough milk. That might become a reality, you know?” says Morgan.

The band-as-a-brand model isn’t new, but the gold standard has come from American R’n’B and hip-hop – genres whose key figures have always had a nose for business. Artists as varied as Odd Future, Solange Knowles, Janelle Monae, Brockhampton and of course Kanye West have used music as a starting point for their own brand galaxy, bringing on tight-knit teams of collaborators to help realise their expansive vision.

Client Liaison is no different. In fact, they might be the only act in the country to have an actual office. “I never thought I’d be running a small business,” says Morgan. “Not that I do it myself,” he says, referring to a team of stylists, producers, set designers, tech wizards and “off-white-limousine” drivers who make it possible to be open to anything as long as it’s “on-brand”. “Our office is humming at the moment.”

“When we work with other people creatively, we’ve already established the Client Liaison narrative. It’s ongoing. Everyone knows the core themes, so we’re always on the same page,” says Miller, sounding every bit the agency creative director. “As soon as the vision is lost, it’s just mayhem,” says Morgan. “You have to have some level of order.”

For now at least, that order seems to exist amidst complete chaos.

“Okay. You’ve got seven to eight minutes to lie down, Monte. Eight minutes, max!” says manager Adam De Cata as my recorder clicks off. You don’t expand your influence by having a nap.

One of Australia’s fastest-growing brand-bands is running late, and eight minutes horizontal is a luxury Monte won’t be afforded for at least another week, so he wisely ducks away to take it. Miller reappears, having somehow changed into a suave turtleneck and black spray-on pants while the tape was still running.

“We’re going to the grown-ups table now,” says Morgan, solemnly, but still with that knowing wink.

“This is fashion week.”

Client Liaison Deluxe Line will be available to buy online in mid June and will be sold at pop-up stores in both Sydney and Melbourne.