you could also buy a set of pucks for your solid and take the split, the solid, and only the split bindings and just use em for both boards - which should easily fit into most bags (i dunno what the weight limit is tho...
Cutting skins is pretty easy. The best way and quickest way to do it is with the G3 Trim Tool. Inexpensive. You can probably pick this up at any mountain shop that sells G3 product. Just put the skin on nice and tight. Run the guide along the ski edge and trim it. Takes just a few minutes. I think I spent less than ten on my last set of skins.
The other thing that works good is a letter opener. Which Voile and others include as a trim tool.
i dunno if the g3 tool works differently but in general you want to line up the skin with the straight edge of the ski, but instead of just having the metal edge exposed you want to expose about 1-2mm of the base as well. that way after you cut the sidecut edge and slide the straight edge back where it wants to be the sidecut side of the skin won't cover the metal edge on the sidecut side....
if that makes any sense at all... there are vids on youtube.
It does work differently that is why I recommended it. You just put the skin on how you would want it. No compensating for the edge. It has a guide that runs under the skin. Push it flush against the edge and run it down the ski. You're done. It's really nice. Maybe the best $4 I spent on splitting.
I bought the Spark R&D skins, which came with the G3 trim tool. I just wasn't quite sure if I was supposed to trim the inside edge too, or at least just make sure there was a bit of edge/base showing there as well.