Regarding hardwired dash cams, motability allow it if installed pre collection by dealer. When my dealer called to say car had been delivered to them awaiting PDI check I asked them to instal dashcam from their accessories brochure. So on collecting car the dashcam had been installed. Surprisingly dashcam was same price as retailers and charged £30 installation fee and that includes hardwire kit and sdcard. Plus any wiring or loose trim issues fall back on dealer. Downsides are you are limited to which dashcams are offered by your dealer