Can you rent a bigger van or go with more then 1 vehicle? I would also try to go with less if possible and do laundry mid trip. I know you said that you will be gone for 2 weeks and do not want to do laundry, but dirty clothes can really start to stink after a while. I can't imagine what 7 full suitcases full of 2 week old dirty clothes will smell like. Especially if you are taking home any food souvenirs, it can really permeate anything it is in contact with. I know that most people don't think of things like this, but I travel quit a bit and for longer trips so it is one of those things that I factor in.