He was active in the Sydney art market, before his death in retirement in Bangkok on 1 July 2024, at the age of 91.
Stern grew up in the suburb of South Coogee and attended local public schools.
In April 1959 he opened premises at 217A George Street, Sydney, and named the gallery the Museum of Modern Art.
In 1962 an oil on masonite board portrait of Stern by Judy Cassab was hung in the Archibald Prize exhibition at the Art Gallery of New South Wales.
From the 1970s until the 1990s he often opened his galleries and his historic five acre garden Kewita at Somersby, New South Wales[6] to aid the National Trust, Eryldene Trust and the Black and White Committee, who raised funds for the Royal Blind Society of New South Wales.