Depends on where you are going and your accommodations. I took it with me on a trip last year. We had a kitchette supplied, so it wasn't too bad. Also, we were staying at a college, so between MF and cafeteria, wasn't much difference.
If you have a microwave or hot water available, it shouldn't be too hard. You could also see if you can find a "hot pot" to take with you for warming up water. Maybe order some extra snack bars to take with you for if your outta touch with your room. Also, I got a glass with a little mixer attachment at GNC. Worked well on the shakes.
As for motivation, all I can really say is, "Do you want it bad enough?". Then again, that goes with this program(or any other) on a daily basis anyways. Of course, if your vacationing at the beach, all those hot bodies should provide inspiration enough.
Good Luck and Have Fun!!!