To give home owners extra reassurance that you're not a member of the criminal fraternity, it's a good idea to commission a copy of your very own police check, or in other words, a statement from a government authority that proves your "lack of a criminal record". Having this available shows home owners that you're serious about presenting yourself as responsible and trustworthy and may put you ahead of the competition.
The process of commissioning a police check (known variously as a 'criminal record check' in Canada and a 'police certificate' in New Zealand) varies but is a fairly straightforward and inexpensive process.
Your criminal record check should be current (preferably less than one year old).