@John *********
ok thanks. So just to clarify and hypothetically if we started our dtv visa with enough money to live for 360 days (first stint including extension) and all out income sat in a separate australian account we should be fine.
Also you seem to know what your talking about, will the plan to do the extension straight away, finishing close to the end of the calender year work for resetting the 180 days and allow us 1.5 years there in total with a small break?
Appreciate the help