Steps

1. > Whether in your country, or those on the border, or even further, you have to prepare yourself
2. Update the car's GPS map (to get an idea of turns and others, because they can be out of step)
3. Update the GPS map (offline) in Google Map (to have an accurate version)
4. Find out about the limitations (and respect them)
5. Various locks (for bridges and other romantic places)
6. Pens and indelible markers
7. Sopalin
8. Download languages (offline) in Google Translate
9. Food and drink in a tote bag (put on the floor behind)
10. One charger per person
11. One external battery per person
12. Cash per person and per suitcase
13. A sweater (even if it's supposed to be hot)
14. An umbrella (even though it's supposed to be sunny)
15. Sunglasses (although the weather is not supposed to be sunny)
16. Electronic toll (if you have)