You're exactly right. A company gave me tour of their products a week and a half ago, and the installation cost is about $650 per unit and $25 per month. They had an option to add on a screen inside the vehicles so you could use it for navigation, otherwise it's out of sight under the dash. One other feature is the integration with the vehicle's computer to tell you if the engine is reporting a problem (oxygen sensor, etc, etc), what your fuel economy is, and how many miles until the next oil change or service stop.
Cost effective? You tell me. At this point, for us, definitely not. In an age of information, so what if you can tell me more about the crews. I need to be able to use the information without working harder before it becomes a way of saving money. It would have to be integrated with our systems to verify the job start and stop times based on when the vehicles left the jobsite before I would see the time tracking benefit. Otherwise, you have to hire someone or reassign someone to go over the handed-in paperwork and compare with the GPS times. T-e-d-i-o-u-s.
Very cool to be able to see where all the crews are at one time. Great to be able to track it if it were stolen, but does that add value to the bottom line after subtracting the cost?