回複：- 問個去加拿大(第三國)的美國領事館簽入美簽證的問題

Yes, you need to have an id to get into the site to view available date for visa appointment. But they won't charge you until you book it. Yes, the phone number is 900 number, you have to pay. But everything you need is online, it is useless to call them. As long as you have employment verification letter, your most recent pay stub, I797, you'll be fine. The only risk you may have is background checking which may take 2-3 weeks. But not everyone encounters backchecking.