Hi,
A creditor linked with an apartment building company started to contact me by phone 2 months after I moved out for an alleged debt (unpaid rent). They started by calling me 3 times a day, followed by once a day, and are also contacting a U.S citizen and my grand-mother. What are the statutes of limitations as far as how long they have to initially contact me? I read that they must first send me a registered letter, but have failed to do (they have a fowarding address). What recourses can I take to make the phone calls stop?
Thank you for your time.

Statute of limitations has nothing to do with this. If you owe this debt, they can attempt to collect it until its satisfied.

This site outlines the rules: What to do when the Collection Agency calls.

Not sure what you read but read this Canadian Debt Collection, Creditors' Remedies... They can call you a great deal as long as it is not at an unreasonable hours and who is to say what that is. You didn't tell us, do you actually owe rent, or any other fee?