My cam has no batteries, no internal storage, no LCD screen, and no GPS - although many cams do. I paid about $200 for mine but other cams with more features go as high as $500. Mine has since been upgraded:
http://www.ebay.com/itm/IROAD-IONE-3800 ... 377wt_1194
There are even cams with two lenses - one records in front and the other records what is behind you. It mounts near the top of the windscreen with a clear cradle so it doesn't get in your line of sight whilst driving. The power wire is then run along the top of the headliner and down the driver side pilar to either the fuse box or to the cigarette lighter. You never need to remove the cam from the cradle unless you want to. The cam records to an SD card that can be removed to view footage. It can record 24/7, only if an event (shock) happens, or by switching on /off. It will continue to record until the card is full - then it begins recording over the oldest files so that the most recent files are always available. You simply remove the SD card and insert it into the card reader (included) and plug that into your comp to download any files you want to keep.
Here are some pics of my install:
.

.

.

.
