We have them, I forget the one we use now but did use this one for a bit…
https://www.pinpointpal.com
Yes its hidden on the vehicle but we clearly mark within the cab under the driver’s nose "this van is tracked" blah blah blah…
Its not big brother, its trying to run your business effectively as possible. if the driver knows from the first time he jumps into the vehicle he is being tracked. there is far less chance of him doing anything he shouldn’t be. You also have the added security aspect and plus your Insurance may discount you on the fact you run trackers.