Landlord refuses to do work!

[Maya Torres]

I property manage (unlicensed) a duplex for a friend who was stationed overseas. I manage my own duplex so I have some experience. Anyways. He refuses to do any repairs in one of the units whose tenant is complaining about a mice problem and a legitimate shower head issue (I verified). She pays her rent but never on time always with a late fee. He refuses to allow me to call anyone to come and fix the issues. I think it’s because he considers her a problematic tenant and a “liar” that he’s refusing to fix anything. I would never do this in my own units and I’m kind wondering ...where am I going with this?