A backpack on the back, about 6 Kg.
2 Full suspension bikes 26 inch:
No luggage rack at the bicycle!
Mostly in hotels or bed and breakfasts.
In Switzerland there are so many hotels, you even don’t have to reserve them in advance. Book it for the next day with your smart phone, e.g. with the Booking.com app. Especially the big hotels offer reasonable prices if you book late.
In France it becomes challenging. It is large and it is empty. You can be happy if find something. Reserve in advance! One day in France we added 30 Km and several hours onto our tour in order to find something for the night. This is annoying, and the mood goes down.
This is easy. Smart phone on the handle bar. Good outdoor maps and Gps track preloaded from here:
Download Hiking Map Via Podiensis
Download Hiking Map Camino Frances Santiago
and then simply follow the blue line on the device. The maps contain way types, accommodation, elevation lines, shopping,… all you need for your quest.
The battery last easy for a day, read more here:
Smartphone Outdoor GPS Navigation