My neighbour has built a decorative wall completely on my property. he is claiming it's a rety wall. I am not sure what it is. I've an identification survey as well. The encroachment is 21cm excluding the footing. I'm not sure how big is the footing as it's underground. He is not only refusing to move the wall but also denying the encroachment. He built the wall in 2017 August 30. We moved to the property on July 1st 2018. At the moment the case is in NCAT. But NCAT wants both parties to prove whether or not that it's a retaining for them to decide on the jurisdiction. What options do I have?