I am sorry to hear that it has taken so long to get a functional bathroom, must be tough!! The answer lies in the lease - did you sign a lease? Read through the lease carefully and find out if it mentions anything about renovations and the remedy period in which those renovations are taking place. I have seen landlords use a clause that guarantees a problem will be fixed within a certain number of days and no rent is due until the situation is resolved. If I can help further, send me an email at firstname.lastname@example.org. Thanks!