I am a Surveyor but have not done any survey work for 20 years or more. The nail in each peg is the actual AMG (Australian Map Gid) coordinate . The fence is built so its centre line matches the string line between the 2 nails. In reality just get the fence close to the line and its OK. If you an your neighbour build the fence then you are both in agreement and there will never be any issue. Cooperation with neighbours is a must in this case and 5 cm of land has be fought over in the courts on countless occasions. A fence that has been there for 20 or 30 years is the boundary. The evidence of occupation of the land is the fence line. A Surveyor simply uses the existing evidence and previous survey marks and occupation to recreate the boundary. Hence many legal battles. In SA and the ACT the coordinates have more legal weight than other prats of Australia.
