You must pay for however many users you feel you will need while training. For instance, if you have 20 technicians on staff, you might want to train 3 of them at a time on how to use Mobile, so 3 users would be fine with starting out since they could all share the licenses. Same goes with your office users. You can go up and down users anytime, so if the count is not right, we can always adjust it for you by calling your sales representative.