Chevylvr,
Others will have to let you know for sure about the voltage. I did see posts from various others about sets that had either voltage. One guy wired up a 220 outlet by working at the breaker panel to bring two separately phased leads together to run to the outlet. Will be interesting to know how that does when the AC and water heater are running together during a drying cycle.
About the vent. Our 3475 is prepped for a W/D, but there's no outside vent installed. I've walked through other prepped models at dealers, and none had the vents anywhere to be seen. I believe that's probably something that happens when someone takes the plunge and installs a dryer. Maybe it needs to wait, depending on what model one gets.
We used the space for a freezer. I'm tired of going to laundromats. But, I can now find solace in ice cream, and/or sno-cones!
Steve