Ever travel abroad with your NF?

Hi! I'm new to the nannying world and landed a really sweet gig with a lovely high-profile family. They are good people who care deeply and wish to take care of me as I am taking really good care of their little one. They have just one baby, a little less than 2 years old. We are all a great fit for each other.

They recently asked me if I would consider traveling overseas with them to perform nanny duties on vacation. I said yes, and I offered up to a week of my time, which they were excited about. Frankly, I'm excited about the idea of it as well. It's travel plus caring for a baby - two things I love most.

WHAT I NEED HELP WITH is understanding what on earth to have them pay for. I assume it would be everything: airfare, my room. meals, and my regular 9-5 wages, or whatever hours they have me working while there. How do I set expectations and talk about billable hours? What if they want it to be fluid and I'm off for some hours, then on for some? I have no idea how to go about having this conversation (nothing formal has been set in stone, and no formal conversations have been had yet) and I'd like to be prepared for when the time comes.

If you have had the chance to travel abroad with your NF as the nanny, please explain how it went, how it was structured, and any suggestions you might have regarding any of the above questions or information. Thank you, thank you!! I'm excited but nervous about hashing out the details, so any help is greatly appreciated!