1 E-Verify Demonstration Video - A quick Overview in 3.5 minutes. E-Verify is fast, free, and easy. The video is a demonstration of using E-Verify to run a query on a U.S. citizen who presented an unexpired U.S. passport with his I-9 Form.  Video: The Truth About E-Verify, a Fox News report (July 14, 2010).
The current registration fee to take the MCAT is $300. The current registration fee to take the DAT is $415. Students who are experiencing severe financial hardship may be eligible to apply for fee waivers to help defray the cost of taking these admission tests.
Alex provided a good estimate of $30-40 per month. So, to answer your question of how much it costs, there are a couple of considerations. First, there are the upfront costs, which as Alex said, can be as little as $100 for ADT and go up from there. Then, there are the recurring costs that are charged monthly. If you consider that you will be forced to sign (most common) a 3 year contract, then $30/mo. x 36 months = $1080 + your installation costs.