We did this last year, cross-country with pets in the car! I’m not going to lie, our car was stuffed to the max, but I really don’t know what I personally could have done without the stuff we had with us.
Here’s what was in the car with us:
Clothes for a couple of weeks in case of delays with the movers, plus towels!
Pet food, supplies, toys, carriers
Cleaning supplies for when we arrived – paper towels, windex, dawn dishsoap, garbage bags, dishclothes, handsoap (obviously you could just buy this new when you arrive, but it was nice to have essentials with us and I hate to re-buy stuff I already had)
I brought 4 place settings of plates, cups and cutlery because I can’t stand paper plates. It barely took any room and felt so nice to eat off real plates in our new place.
Paranoid as I am, I insisted on bringing all our family photos in the car with us. If anyone was going to lose them or destroy them, I rather it be me than some moving company. We also brought jewelry and important papers like social security cards, passports, birth certificates, etc. in the car with us.
Inflatable mattress and sheets and our pillows. Plus a thinner comforter that rolled up nicely in the car.
This may be overkill to others, but to us it was essential… our computers. Both mine and his. We live on our computers and we watched all kinds of movies on them while we were without tv or furniture. Had one set up in the bedroom as our makeshift ‘tv’ and it was great even before we got the internet hooked up.
You don’t have to be as packrat-y as me, but it made it very nice on the other end of the trip. Oh, and obviously pack some snacks for the car so you don’t spend a fortune on crap food every day. We bought a big jug of water at the grocery store for $1 and it was great for the road.
edited to add: we packed a very, very makeshift kitchen set up. one pan, one spatula, one cutting board, one very sharp knife.