Here is Dalhousie University’s Tenant Rights Guide, covering rental housing in Nova Scotia.
They advise that a written roommate agreement for all items of any importance is essential. This will make it much more difficult to dispute anything already agreed upon after the fact. It would also make it easier to enforce in the worst possible case scenario, if you have to go to court.
There are a few more paragraphs of advice, read the whole thing if you like! But another essential component would be this quote:
“If more than one tenant signs a lease, the law says that they are “jointly and severally liable.” This is a legal term that means roommates are all responsible for the lease, but at the same time any one roommate could be singled out and held responsible for the whole lease.”
This means the landlord may OR may not go after you for something your roommate did or didn’t do (like pay their share of the rent).
Basically, the ideal roommate situation would be someone you feel you know well enough or have enough of a sense of interpersonally that you could trust them to remain financially ethical during a conflict or disagreement . . . but then NEVER get to that point because of your initially assessed compatibility plus good behavior as outlined in your written roommate agreement.
But any and all signed contracts could become important if you had the misfortune of picking the wrong roommate.
Do you need to find a roommate in Halifax or Dartmouth?