If a landlord is just accessing the property for inspection they can go onto the property outside which should be no problem but legally they are required to let you know 24 hours in advanced otherwise the landlord can be in trouble for trespassing even though the landlord owns the property.
When a tenant is renting a place the tenant is part owner until the lease is up on the rental place.
So the landlord must ask permission from the tenant 24 hours in advance before entering property and you must allow the landlord into the place after 24 hours notice to inspect if it's in your lease.
However during an emergency situation the landlord can enter the home or apartment without notice and without permission to make emergency repairs.