I think the Carte Orange transportation pass is the most convenient and least expensive pass to use. You will need small photos... just have extra passport photos taken. We had ours taken for about $14.00 at Walgreens. The Carte Orange begins on Monday and goes for a week... for those days which the Carte Orange doesn't cover, the Mobilis Ticket serves the same purpose, but you will not need photos, and it's only good for the day. However, say you arrive on a Saturday... purchase Mobilis Tickets for Saturday and Sunday and a Carte Orange for the following week, and you're covered.