Homeowner refuse selling house

The property in The Ponds, Sydney, Australia: https://www.google.com/maps/@-33.7104098,150.8954086,1240m/data=!3m1!1e3

Bird's-eye view:

https://www.google.com/maps/@-33.7101843,150.8953251,3a,75y,248.32h,59.75t/data=!3m8!1e1!3m6!1sAF1QipNmc4CGEZePjthBWV6pNjvVyxZ3D0xn2m9DM9py!2e10!3e11!6shttps:%2F%2Flh5.googleusercontent.com%2Fp%2FAF1QipNmc4CGEZePjthBWV6pNjvVyxZ3D0xn2m9DM9py%3Dw203-h100-k-no-pi0-ya100.22243-ro0-fo100!7i8192!8i4096

Street View: https://www.google.com/maps/@47.662205,-122.375384,3a,75y,358.63h,84.23t/data=!3m4!1e1!3m2!1slB3jsbSE7--QIoXnwwrU9g!2e0