The start of a new build in existing areas usually starts with demolition of the existing house. At this stage it's good to establish with the neighbours the existing fence lines and that they are in the correct place. 

Also any existing walls on the boundary that are part of your garage or house that need to be demolished, these will need extra attention as it will leave both properties open to each other and the neighbours may have installed clothes lines, hot water units or sheds connected to those walls.

Once organised the demolition should take around 3 days to complete onsite.