That was five years after the couple took over the popular galleries, initially founded by Ron and Betty Beaver in their Red Hill home in 1975. Later, the Beavers and the late Joy Warren of Solander Gallery, were offered allocations of land on the southern side of Adelaide Avenue, then overgrown by gum-plantings, where they built their purpose-built galleries, designed by Martin’s architect brother Ross. The rest is history.

In the earliest days of Beaver Galleries, decorative arts and music were to the fore and even now Betty, a musician herself, sponsors the “Beaver Blaze” in the Canberra International Music Festival.

But the younger Beavers had a different idea, one that has proved remarkably successful, with a balance of fine and decorative arts providing a solid business basis.

When they took over, their first child was three months old and now she’s due to turn 24, growing up in the gallery until the family moved offsite. Times have occasionally been hard, but as Martin says, “in real life, stuff happens.”

“If it hadn’t worked, we would have stopped a long time ago,” Susie adds.

When we catch up, the Beavers are in the midst of a sellout exhibition of landscapes by the late Andrew Sayers and an unusual show of works by cartoonist Judy Horacek, including works on clay.

But normally they have a stable of favourite artists, people such as Helen Geier and Madeleine Winch, as well as fine artists in glass, ceramics and textiles and jewellery, some exhibited as art and some purely for sale.

They believe that over the years, part of their success is attributable to the fact that they’ve been galleries, reasonable and affordable, in an intimate setting.

“There is an ownership factor with people coming here for a long time,” Susie says. “They feel as if they’re a member of a club.”

Martin and Susie Beaver regard the marketing and business side of running a gallery as an art in itself – “you have to be sensitive to the market,” they say.

With that in mind, Martin has often travelled to the Sculpture Objects Functional Art and Design (SOFA) Fair in Chicago, but nowadays they consider the Melbourne and Sydney arts fairs more workable for them.

As for their regular stable of artists, they say, “every now and then there is a little bit of attrition – you have to be completely hard-headed in managing such business, you have to show work that is really worth showing… it’s a massive risk.”

When they first took over from Betty and Ron, Susie says: “We romantically thought we could work together”. They’re still there with the help of their “fantastic young staff”, but say they don’t have a succession plan.

“So long as we still have the passion, we’ll be here, it’s something you take as it comes,” says Martin. “But we won’t be here in our Zimmer frames!”

Beaver Galleries 40th birthday celebration and opening of “Small Works 2015” exhibition, at 81 Denison Street, Deakin, 6pm, Friday, December 4.