Our customer recently traded in his vehicle for this Prius Prime so we transferred his Thinkware F770 from his old car into the new car. We added a Cellink dash cam battery to his setup for extended parking recording. This battery charges while driving and works as a standalone power supply for the camera when it's in parking mode. The benefit to this is that there's no drain on the car's 12V battery and no interference with other systems that may run on that 12V battery while parked.
The battery fits neatly under the driver's seat and is out of sight once the seat is slid into a normal driving position. The rear window and hatch design is unique for the Prius Prime as it has an indent in the rear window. Because the surface area of the rear camera tape is fairly small, there's no issue mounting on the curved window. We mounted the camera at the top of the windshield which still provides a fairly clear view, although the beam/spoiler across the rear hatch does impede the view a bit. The carbon fiber trunk on the Prius Prime does not have any plastic trim to hide wires so running the wire down to the smaller rear window would be quite unsightly.