I'm planning on ordering 3-day passes for us online ahead of time. (1) For any of the bus passes: does the passenger scan them through a bar-code reader when entering the bus, or just show them to the driver, or what? I figure we have to scan them through something, sometime, to start our 3-day period; and (2) I think we'll be embarking/disembarking at some of the "shared stops" (both SDX and the Deuce use the stop). In case I am (a) bedazzled by all the people and lights and goings-on, or (b) drunk, am I correct in thinking that the Deuce buses are always double-decker, and the SDX buses always double-.....trailered? (don't know how to word it - I think the photos always show a bus with a front and a back ..... trailer. Oops, one more. Etiquette and standard practices: do passengers always enter from the front and exit from a back door, or is it a free-for-all?