We travel home 2-4 times a year, for periods of 4-14 days. Out of necessity, we take our furballs with us(2-4 rats so far, although our max is 6, and travels will get interesting if we ever have to travel while we have that many.) For such a short trip, the double CN gets left here, and the rats travel in wee travel cages(12 hour drive) and then survive in a smallish cage while we are staying with family. Smaller than we would ever be willing to let them live in for normal day-to-day life, but bearable for a week. When we were boarding in Indiana for 3 months, we took half the CN for three rats, which was easy to take care of and clean up. Make sure to take enough food for the trip, any medications/supplements for the rats, and enough bedding for necessary changes if you won't have access to laundry facilities. Familiar toys and treats can lessen their stress in a new space. As long as they have you there, I really think taking them with you is less stressful than leaving them at home with a stranger coming over to feed them for a week with no out time, difficult as it is to find someone that is comfortable with taking the rats out for playtime.
For the actual on the road travel, its important to make hydrating food available in the travel cage(apples, grapes, tomatoes) because hanging a water bottle in the car equals a very wet cage and unhappy rats. Our rats won't even take a bottle while we're stopped, and tend to ignore their block(though we make sure there is some in the cage) but they are always excited for a piece of fruit. Younger rats were interested in coming out of their cage, although they then didn't want to stay with me in my lap, they wanted to explore, and loose rats in the car is dangerous, both to your car if they chew, and to them if you are in a wreck or even have to slam on the brakes. Rats over one year, especially who have been subjected to "the bouncy move-y thing" as it is known in our household, before, will usually sleep the whole trip, only occasionally getting up to see if we're there yet. =) If it's cold and or raining while you are transiting to and from the car, an old blanket to cover the cage is a must. If your doors don't close well, or you have escape artists that occasionally pop their doors open, consider using zip ties to make sure they don't get out at a really bad time, like when you stop for gas. :wallbang:
I think the only real deal we've had with travel is making sure there is safe out-time space in your new/unfamiliar space, and sufficient out time. Staying with our parents, there are dogs and cats in the home to contend with, nice furniture that shouldn't be peed on, electrical cables that haven't been obstructed for safety. We are often out all day, visiting friends we haven't seen in forever and trying to fit in as much family time as we can while we are home. We make a point of setting aside time for the rats. Our rats are couch/bed trained, so we usually just put down an old blanket and let them scamper on us for an hour + before bed time, and again in the morning if we are free. If your rats are used to jumping down into the floor, be sure to thoroughly check the space beforehand as you would your home, for cords, holes, and anti-rodent devices such as traps or poison, which are often concealed in small unmarked cardboard or plastic boxes.
If any of your fuzzbutts are on medications like antibiotics, make sure you have enough to carry through your trip, or even better, extra on hand in case someone else comes down with a URI while you are away from your regular vet/pharmacy. If you have an awesome vet, they might be able to call something in for you in an emergency, but there are no guarantees. We keep a basic rat e-kit on hand, with dark chocolate, infant ibuprofen, our vet's phone #, the recipe for hydration solution, your know the drill. I used to be a girl scout, and always prefer to be over prepared.
Sorry for the long post, just my musings as we've been traveling with rats for as long as we've had rats, so its familiar territory. Good luck with your holiday, I'm sure it will be enjoyed by all! :dance: