The earliest photo I have is this one with rather vague date of pre 1900. Looks like some sort of working bee maybe for the church which was opposite and can be seen in the next photo. The Presbyterian church was opened in 1892 so I think this photo has to be earler. Note the house is more or less square with just the front veranda and seems no to have a chimney although I expect the coal range was there in the kitchen at the back
The history I've collected so far is based on talking to Errol Jones who has also written a book on her family history (Shadows on my Wall) and Austin Smith who provided the photos. It seems the first owner was Lovelock and Mary Cozens who were married in 1859 and the house was probably built around 1866. Lovelock's parents (also Lovelock and Elizabeth) arrived in New Zealand on the Cashmere in April 1857 so the timing all fits. The house originally had a shingle roof which also confirms it being built in the 1860's as corrugated iron wasn't imported until the 1870's.
In the picture the chimney is visible as is the church opposite (at 4 o'clock in the picture).