Ah commercial, so once loaded on the carrier, even if the friend is the driver, s/he won't have easy access to the car so it'll have to be set it and leave it. Lots of factors to consider. Unless the friend loading the carrier is accommodating, the car could end up on the lower level or somewhere other than at the front of the upper level. And given the varying angle of pitch of the deck, you won't know where to aim the camera. Right, so smartphone isn't practical.
Another option, though it requires a not insignificant outlay, is a
Spot Messenger gps tracker for the unit and the tracking subscription. Generation III takes 5v USB power and the tracking can track indefinitely (previous versions only tracked for 24 hours then you had to turn tracking back on). This will give you a location every few minutes (user setable) but no pictures. I have a Spot II and it works great for location. Delorme makes a similar model that gives velocity but the subscription is more expensive. I've also tracked with a Garmin GPSMap76 or similar (seems the current model is up to "78" now.
https://buy.garmin.com/en-US/US/on-the-water/handhelds-wrist-worn/gpsmap-78s/prod63602.html Expensive to buy for this project, but an older one might be around. Takes 12v power and any memory card will be sufficient to track the route and it'll track indefinitely until the card is full. But still though, images would be neat to capture if it's possible. A handycam video set for time lapse?
For power, if you don't want to run GPS or dashcam off the car's battery, there these
battery packs for USB power I've considered for running dash cams for long periods in parking mode to completely be isolated from the car battery. Largest is 20,000 mAh for about $100.
Good luck.
