Look at the Raspberry Pi computer.
In fact, I am typing on one right now.
The one I have has 4 USB ports. 1-LAN connection, SCD card, Wireless network and a camera port. I probably would use USB cameras. I have a 1T USB hard drive that works with it.
The point is that in a car it is a small computer that knows USB, network, etc but when you are developing it connects to a USB keyboard & mouse and any HDMI monitor and becomes a PC. (you have to use open office not MS office)
The Raspberry Pi has a power down mode where it pulls little power. The advantage is that you do not need to know how to connect to a hard drive or USB camera. The operating system knows.