All dashcams record as soon as you start the car, if you also want that to happen when you are parked that is also possible by turning on parking guard. ( hard wire kit needed to enable parking guard )
But there are still some issues to be mindful of, first and foremost power use while parked, and the fact you need to drive some too every day to charge up what you lost while parked.
Also the modes systems do parking guard in are hit and miss, at the bottom is motion detect, this is always too sensitive, so parked at a place with stuff going on, and the system will pretty much record all the time.
So do the always record in low bitrate do, but not all systems have this mode, it is what i use, but mind you only for 3 hours on a timer in the system, i am not entirely sure this will be good for really long durations.
A big + is you can have the G-sensor on too while doing low bitrate, so any actual events / your car getting hit should prompt the camera to lock that file in the event / read only folder.
For sure you want a big memory card, 256 GB at the least, 512 GB are also a option with many brands today.
Low bitrate mean much smaller files and so room for more, also in the daytime with sun, well doing low bitrate mean the camera do not generate as much heat on its own, but electronics only go so far with temperature, when the max is hit they will shut down to preserve them self.
Heat endurance is also a question, depending on where you live, as you know a car get uncomfortable hot in summer sitting in the sun. So that will be a limiting factor on those days.
There are not really any side cameras in dashcams, but some of us have adopted to have that, this be filming strait out the side of the car not down the side of it like you will see Tesla cars do.
Strait out the side is also fine, it will catch just about anything approaching your car.
This was my setup when my side camera system still worked.
In my cars the side camera was another brand than the F&R system, so they boot at different speeds so the footage are not in sync.
Some will use 2 similar dual channel systems, and then put the main units on the front and rear glass and the little remote cameras on the side, that way the systems should boot in the same speed and so be in sync
As for the side cameras, well you cant put them on windows that can go up and down, so in my case p put my side cameras on the small fixed glass on my rear doors.
A issues here could be meddling child fingers, but if thats not a issue you can get a bit more creative with the install, but you probably need to get creative CUZ as i said not really any side camera systems that is dedicated for that.