Carrier Bags

I'm flying to New Zealand soon, and am taking two different airlines. One to get to LAX, and American carrier, and then a NZ based carrier to get me across the ocean. I'll be on the American plane first, and they charge a checked baggage fee of $15 for the first bag, and I'm only taking one. So $15 for my bag. Do I have to pay the NZ airlines baggage fee as well, after I've paid my other airline's fee? If I do... I won't come back into possession of my bag until I land in NZ obviously, so how would I even pay this?

I've got lots of wraps and things but I want to get one of those walking carriers for the back - I've never actually seen any though and don't know what they're called so don't know where to look! Can anyone send me a link? Preferably British but even if it's American it'll still be useful just so I can have a look at it!

My design brief is to design and make a sales pack for a high street fashion store which includes a logo, colour scheme, swing & price tags and a carrier bag. I am now doing a specification, and we have been told that it needs to be detailed and justified with at least 12 points. Please help! I've only got 2 points so far.