The property is in MN. Other than the lease the general rules for MN are as follows for entry into a unit.
1. Showing the unit to prospective tenants
2. Showing the unit to a prospective buyer or insurance agent.
3. Performing maintenance work
4. Showing the unit to state or local officials inspecting the property
5. Checking on a tenant causing a disturbance within the unit.
6. Checking on a tenant the landlord believes is violating the lease.
7. Checking to see if a person is staying in the unit who has not signed a lease.
8. Checking the unit when a tenant moves out.
9. Performing housekeeping work in a senior housing unit.
I basically have to give a minimum of 24 hr written notice or under an emergency clause. I would be using the #3 for maintenance and #6 since I'm checking on that I can get in to the unit since he locked me out. So I'm in my legal right to do so and giving him 2 weeks notice to think about his actions is more that sufficient if I ever end up going to court. I wasn't able to finish my spring maintenance either last week since I couldn't get into the interior of the property to get to the utility room.
I would just end the lease but he's been there 4+ years and generally hasn't been a problem except for entry into the unit. He keeps the place clean and pays rent by the 5th most of the time. He just always makes it a point to be there when I do maintenance. He even missed work so I could fix a toilet handle of all things. I've let that slide and have worked around his schedule other than one emergency over a water leak he wouldn't communicate over about the status. So I went into the unit under "emergency" rules about 18 months ago. I'm assuming that's when he changed the garage code on me.
I figure, if I need the locksmith to open the storm door, I'll charge him for that otherwise I'll eat the cost of the civil standby to make my point.