We are each taking a carry on size suit case which so far has seemed to fit what we think we need. But I'm worried about how much room we should leave for souvenirs? I'm going to try rearranging things later. But I think that if I expand the suitcases (which would make them non carryon, but on the way back we don't care) I can get all our stuff into 3, leaving one empty. Will that be enough for souvenirs? Keep in mind that this is our first trip, we only plan to buy t-shirts, hats, that kind of thing and will buy for ourselves, and our nephew. So what do you think?