As long as the power of attorney meets the requirements of a power of attorney in Newfoundland, states that it survives mental incapacity, meets the normal registration requirements here, references the sale of real property, and a lawyer writes a letter stating that it meets the above criteria, you may sign on behalf your husband and the transfer of land should be registrable to complete the sale. However, to avoid complications, we recommend the power of attorney and other estate planning documents be made and signed in the province in which you live.