I'll pile on and say you should've bought the 6 hatchback or wagon, assuming it's the '03-'09 generation. I know 4 people that have or had the same car, and you have plenty of room to work with even if it is a trunk model. And I have the same grill and it's well worth the effort.
You can find a schematic on weber.com that will give you the best idea, but you should be able to break it down into enough pieces to get it into your trunk and folded down back seat. The lid will come off quite easily and the firebox should be removable from the cart pretty quickly. I believe you need a screwdriver, pliers and an adjustable wrench to get to that point. Those 3 pieces should be manageable. I'm sure it's not going to be cleaned out, so you may want to pack some old blankets and a big garbage bag or two.