Yes in parking mode the camera are always on and using a few milliamps, it don't really matter much in regard to power usage if the camera are recording say time lapse parking mode, or actual 1080/30p footage.
Yes dual cameras record and detect ( if you use that ) motion on both cameras, my car using the K2S test camera recorded this footage while parked at my friends house yesterday, his sister arriving.
As it is now that camera drop to 720p in parking mode though i cant see why it would need to do that, maybe they haven't gotten that far with the firmware yet.
But motion detect are a flawed mode for parking, cuz it don't take much to set it off, and as the other end of my car was facing the highway my friend live right next to, for the 8 hours or so we was putting up his new greenhouse it made a hell of a lot event recordings.
A finely tuned G-sensor will be more usable, and create less false event recordings.
Also these sensor trigger ( motion or G-sensor ) you would want the camera to have a buffer so you get a few seconds from before the triggering event, currently my test camera don't have that, but i think its just a matter of firmware on that particular camera.
Lately it seem like it have become very popular to do regular 1080/30 FPS recording while parked, but then to lower heat generation within the camera itself the parking mode are on a much lower bitrate ( which are fine as long as there are not fast movement to deal with )
The IMO big plus to this approach are you still get sound recorded too, something you will miss if you use time lapse for parking mode. Also as it is recording all the time, then no need for a buffer as what is before the event will also be locked away in a read only file.
In general event files for parking guard go in a RO folder ( read only ) so that folder have to fill up before the camera start to overwrite those event files, just like a dashcam also do with regular footage when the memory card are full.
And don't worry with a proper size memory card ( i recommend at least 64 GB for each camera in a system ) you will have room for a lot of event footage, only something like motion detect in a high event scenario will be triggering so many events that it might be a problem.
Anyway motion detect are not recommended to use for parking mode.
The low bitrate 1080/30 parking mode event files are due to the low bitrate also a lot smaller than regular high bitrate recordings, as a rule of thumb we say a dashcam generate about 100 MB every minute for each camera for regular high bitrate recording ( around 20 mbits ) so low bitrate parking mode which are around 4 mbits will be significant smaller files and so room for much more video in a given size of memory.
I think i would focus on some of the 10 A fuses, if you have it use a multi-meter to test which fuses are live or not, using a old style bulb detector pen are not recommended on modern cars.
I personally use a cheap Chinese multi-meter from the dollar store.
And do remember many new cars keep some circuits on for a while after you have turned off the car, so best to open the door turn off the car and let it sit for a while before you start to figure out which fuses are live always and which are on with the turn of the key.
Street guardians hard wire kit have 3 wires.
First + wire need to be on a ACC fuse that come on / of with the car engine ( thats so to say the detector wire that determine if the camera go into parking mode or regular drive mode )
Second + wire go on a always on fuse, it is thru this one your camera are powered when parked as the ACC + wire are of course off when parked.
And then last the negative wire, that provide - 12 V no matter what mode the camera are in, be sure to use a screw that actually have a connection to the car chassis.
