CCTV signage

[NRGetic]

Hey guys... I'm in Ontario and i live in a condo complex which doesn't have any security cameras. my vehicle seems to be picking up scratches overnight...
If i was to purchase a cctv camera and hide it somewhere in the car to look out the window to see who's involved would i need to post some kind of warning signs? Would it be legal to just film video and not post sign?

I haven't been able to find a clear answer on this as the documents i found are outlines for public places surveillance which i don't think describes me (or correct me otherwise).

Thanks in advance