The problems being created by the tenant likely fall most accurately under the description of interfering with the enjoyment, or other lawful rights of either the landlord or other tenants. This means that serving an N5- giving lots of details about each event and the times/dates when each event occurred or was discovered- would be most appropriate. Damages can also be listed on the N5. It is usually more difficult to sufficiently prove to the Landlord and Tenant Board that a tenant has committed an illegal act, is running an illegal business or is impairing other tenants’ safety. If the relevant witnesses and proof for either or both of these other reasons can be arranged, then you are allowed to serve the N6 or N7 as well. However, if you apply to the Board on all reasons at once, then the normal “fast-track” eviction procedures for N6/N7 get slowed down to the normal pace of the N5-based L2 eviction procedure.