I mention this because in an appeal of a citizenship denial Zhou, Yong v Minister of Citizenship and Immigration the judge reported "[9] With respect to the applicant’s residency and travel, the Citizenship Judge concluded that his statements were incoherent. He stated that he travelled to China several times to take care of his father. He also submitted a few leases to demonstrate his residency in Canada. However, only one lease is in the applicant’s name, and it is for only three months in 2006. The applicant provided statements from a few people who allegedly had lived with him (whose names are on the other leases) but none of these statements were certified by a commissioner for oaths or a notary." http://decisions.fct-cf.gc.ca/en/2013/2013fc19/2013fc19.htmleileenf said:The letter will be given more weight if you get him/her to visit a commissioner of oaths or notary to swear to its validity. Depending on your relationship with your landlord, this may seem like a lot to ask though, so you will have to use your own judgement as to how necessary it is to your RQ response.
But use your own judgement about what is important for your response. For what it's worth, Zhou won his appeal and the case was sent back to a citizenship judge for redetermination. And, speaking for myself, I didn't ask my ex-landlords, living and dead, to visit commissioner of oaths. It seemed like too much to ask.