Camera for Minivan

[GreenMint]

Justa curious one, my school has recently letted a new Peugeot Boxster 16 (I think) seater to collect some students from the farer reaches where bus companies would charge ridiculous rates, however, there's no security on there in terms of cameras and the staff here were looking to fit possibly a dashcam or something similar next to the driver to pan back and show the whole bus for safety reasons of all concerned etc..

Any suggestions or ideas on what might be best? I have 0 idea on this but know some of you are very into dashcame etc and wasn't sure if one could be used for this purpose?

Thanks!