I suspect my tenants father in-law is breaking things on purpose

[Jack B.]

Tenant has lived there for a month and has had 4 service calls. Each one the father in law "finds" the issue. Except the house never had any of these issues with previous occupants and went through inspection without these issues.

Today was the final straw. The father in law sends a picture of water all over the floor in the basement (split entry type basement not a true basement) and his assessment of it. I go and inspect and there is literally no leaks upstairs, no water lines in this section of the house and no rain for days outside and no sign of moisture intrusion from outside. It literally looks like the father in-law poured water all over the floor from a bucket. While there is some water where the trim is at the wall, that could also be from pouring water there to make it look like the source of the water. There is no water damage in the ceiling, wall, ANYWHERE. There is no sign of moisture ANYWHERE other than the floor as if someone poured water on it, 5 gallons of it. 

I call my plumbing guy who will come take a look later today and he agrees if no signs of moisture intrusion outside or leaks from upstairs especially without drywall damage, it sounds to him like the father in-law who is always there and "discovers" these things is doing it.

I've since given the tenant notice to vacate. He is some hot shot dentist who yelled at me to leave his father in law out of it. I told him no, the facts are clear, his father in law is always at the house when this happens and there is never any explanation or cause for how it happened, whether it's today's issue or another days different issue. The father in law sounds like he has some mental health issues and is a busy body going around making up problems...his daughter told me he is a really handy guy and can help fix things around the house if I like and I told them no. Especially since he didn't know anything about plumbing when I asked him some basic questions...I wonder if they were going to try to use him to get a discount on rent for "repairs" he did....

Anyone ever seen anything like this???