Is a dashcam very noticeable - as in, would it make the car more of a target for break-ins because it’s a visible object of value?
(My car door was mildly damaged a couple days ago while parked, and now I wish I’d had a dashcam to confirm who I’m pretty sure bumped it. Fortunately, insurance will cover the repair, but I’m out the deductible and possibly a rental.)
Sounds like what you need is a security camera, but I don’t know if that happened at home or out or you don’t park right at your place or whatever.
In any case, I don’t think a dashcam is going to solve this issue for you. You’d either run down your battery, or you’d have to power it some other way to keep it on all the time.
I haven’t installed my dashcam in my current car but I’d previously wired it so it was always on. There was never an issue with running the battery down or anything.
I once heard my car alarm go off and looked outside just in time to see my idiot neighbor speeding away. I checked the cam footage and, sure enough, he had bumped my car backing up.
There are certainly dashcams at a higher price point with the functionality that OP wants. I have Garmin Mini front and back, which has a parking mode with visual motion sensing and impact detection. Impact does not mean a major crash, it will detect any kind of little nudge like someone misjudging their parking and denting you. Visual motion sensing will obviously give a lot of false positives when parked on a public street, but the battery drain is not that much. You can limit the time it stays active in parking mode so that it won’t drain your battery if you are away for a week, or you can disable motion sensing and just leave impact sensing active.
You need a wiring kit. On top of the cost of the kit, Best Buy charged me $50 labor to install the wiring.
These are also the least obtrusive dashcams I think you can get, they have no keyboard or screen - you use your phone to control them, watch video, and handle video storage.