You will probably want to put this in writing to your landlord, and don't put in some reason or explaination, just make the letter clear about what it is you want. Finally, I strongly recommend you avoid entering into a situation where you are getting a rent reduction for having the guy living in your apartment. You need to set some clear limits with him and your landlord. You might also put in your letter a demand that the work be done only during business hours, and follow through with ejecting the guy at 5 p.m. If he won't comply after you've delivered the letter to LL, then call the police if necessary to limit his hours. Go ahead, ask the lawyer.
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