Tenant moved someone into their storage/utility room

[Steve Staub]

A tenant living in a 4-plex has another person living in their assigned storage/utility in the basement.

Said tenant has asked to have the storage door locks changed because he noticed another door is keyed the same. Upon changing the lock it was apparent this storage room was being used as living area/bedroom.

When tenant was asked if he had someone living in the basement he became irate and said he’s entitled to a 48-hr notice before landlord can enter. Then admitted it was his brother-in-law that just came back from job core, has only there for 4 days and will be leaving in 8 days. But still claims landlord didn’t have right to enter.

Tenant was informed no one can live in an non conforming area (basement/utility room) and can only have a guest stay for up to 7 days before having to places on the lease.

Who is in the wrong and is in breach of the lease?