This is an Iwan Iwanoff in Coolbinia. I would estimate it is a late 50s, early 60s example. Similiar approach to siting as the Golovin house, which rises against the slope, and the same large single pitch roof is used. The entry detail, a curved semi enclosed portico, protruding out the side of the building is great. Quite a large project, so I assume additions have been made.