Firstly see if it’s possible to keep the existing duplex and build another duplex behind. This strategy will be highly dependant on the site dimensions and Council LEP however (Hard for me to know without a survey and researching the LEP).
The beauty of retaining the existing duplex (if possible) is that you retain a lot of value (…[Read more]
My first thought in looking at the drawing provided would be the potential for a battleaxe.
There are a whole host of requirements set out in the Councils LEP (Local Environment Plan) that would either allow this or not.
I would have a quick look at the LEP first to get familiar with Councils requirements, in particular: