Two months ago, my housemate started moving things around in my lockless room while I'm at work to unnerve me to get me to leave. It became worse and worse for a week or two until one day the live-in landlords expensive mirror in my room disappeared, my cards were knocked down, the window handle was left at a strange angle, and the landlord’s paintings in my room were made squint all in a single day. The housemate had also been criticising me more and more about various things until this point.
I asked the live-in landlord to check in my room every now and again to make sure my cards from my mum aren't being knocked over. He said it could have been the wind, so I showed him pictures of how my paintings had also been moved squint that day. He then explained that he and the housemate had moved an expensive mirror of his out of my room into storage while I was out, and that said housemate is our paid cleaner. I mentioned that I had reported the mirror as lost to the police, because if it were stolen it could otherwise look like it was me who stole it. The landlord said he could see how moving the mirror could be seen as an invasion of privacy, and more or less promised that the housemate would not be entering my room again. I confirmed with the landlord that I would only need to give 1 month's notice to leave, and made clear I would probably be moving to another houseshare before the end of my 6-month rolling contract because my bedroom is a bit small for me. (This was to make the housemate think he got what he wanted so he would leave me in peace for a while). I then had peace for a couple of months.
A few days ago my housemate probably overheard me on the phone saying that I have not yet started searching for a new houseshare (this has been a very busy time for me, I still need to get another couple of course applications out of the way, and I could do without distractions until that is done). I think he is now restarting his campaign of shifting things around in my room. Today for example my two pens migrated from one side of the desk to the other, and my bottle of bike degreaser moved from next to my container of used degreaser to be standing on top of it. He has also been starting to criticise me again when the others aren't around.
I need to stall for another couple of weeks at least before initiating my search for a new houseshare. Backpackers hostels are probably going to be closed in lockdown until something like June so are not a good option.
I was thinking of concealing a security camera in my room to record the housemate moving things around for a few days and then to leave an unconcealed dummy camera in my room thereafter. Hopefully that would do the trick, and provide evidence for a harassment complaint should this be another useful way to stall for time. Even if the evidence is disqualified for whatever reason the complaint and proceedings via our local inter-tenant relations office could make housemate back off for a few weeks.
Is this a way forward? Are there any concealable cameras which would sense motion, record for 5 minutes, and upload the recording to the cloud? Would I be better with a nanny cam or a deer camera? I don't really know anything about these things.
NB, Context: The relationship between the housemate-cum-cleaner and the landlord is that they are buying a yaught together and the housemate tends to bully/constantly criticise the landlord. The relationship between me and the landlord is that he tries very hard to make me comfortable and happy in the houseshare, and that I put up with him trying to flirt with me every couple of days. (We are all male and they are both gay). It has crossed my mind that the landlord’s flirting could make the housemate feel jealous/irritated (although it's not clear they are in a relationship). The housemate has something like OCD, has told me about how he enjoys getting colleagues fired at work, and both landlord and housemate have told me the housemate was a cartel Scion before his relatives started getting bumped off and he had to flee his country. I am in my mid-20s, housemate is around 40, and landlord is in his mid-50s.
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