A Power of Attorney can be registered at the Land and Property Information Office. The cost is about $130 to have it registered. The registration process does not require the signature of the person giving the power so it can be done at any time, even after they have...

It lasts until you either: Cancel it. This is called 'revoking' – see above. Pass away. A power of attorney ceases to have any effect after your death.

Yes, at any time (provided you have capacity) The procedure is to advise the Attorney that their authority is cancelled. To avoid claims that this was not done, it is best to serve a formal "Notice of Revocation" and register it at the Land and Property Information...