Currently in Christchurch helping my elderly mother with a situation, regarding fencing, boundary and talked with lawyers.
Owner of house next door is well known developer that has been on news multiple times.
1.Sent us a fencing notice. We sent proper (within timeframe) cross notice abiding by the fencing act rejecting due to insufficient evidence and we believe it was wrong document (it was, IN FACT: the surveyor's license was REVOKED).
Tore down the fence claiming it was their land and they have their rights.
Now in a financial predicament, either accept our lost land, or hire a surveyor and lawyer. Thing is if they did have OFFICIAL legal surveying documents we wouldn't even have to go through this, however its common to bluff apparently.
Talked with a few friends within this industry and lawyers and it seems to be quite a common thing to do as the finaical pressure on the landlord is massive to defend and regardless their cost if they lose is only moving the fence back. All the false documentation and misleading is wrong but nothing legally can challenge it as in the end it is not the owner who is at fault and at most the building contractor.
Edit: To make it more egrigious it aint just us its all the neighbours surrounding him. They claim all of us neighbours are encroaching on his land and he has his rights.