HI, you should not be going into her room without her consent. Period!! With regard to the notice period, three months is more than ample.
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When she moved in we agreed that if I will have to do anything with the windows I can go into her room. Unfortunately I don't have anything in writing. All rooms in my flat are opened all the time. I even leave the door to my bedroom wide open. You are right I should let her know, but I would never think it may be a problem. Winter is coming and one of the windows wasn't closing properly. I have found out how to fix it and went there to do it. Because of previous issues it just created another argument. Thank you for your reply.
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