France:
Country of most costly toll highways and fuel. In 2015.11 1l of diesel was 1.15 €, today, 3 years later it is good luck to find it for 1.50 € /l. While prices of veg oil in DE in REWE and ALDI shops I’ve bought for 0.99 €/l;
½ an €  saving on liter, means to me saving at least 6€ each 100km; The system on making dual fueling for camper is in God’s will;

Petrol Stations (ATTN!):
Very rare on toll-free highways! Must keep some litres of oil, just in case running low on fuel, to reach nearest petrol stations: can be met, if highway crossing bigger town. In many cases this will be self serviced, card payments only. If there will be a booth collecting cash payments, remember: cash payments booth collectors have limited working hours. Presumingly, might close at 8pm or even erlier. I’m poretty sure, there should be minimum amount on payment card, as the amount of payment is reduced only after refillment. Presumingly 150 € at lest (have to check; failed today with amount 60 € on card);

Google navigator:
Is the best choice. Saving internet is very possible – use only to set up the route and go offline, while navigator takes through while offline. So far, taking google suggested routes (toll-free) is the best ride through France I remember (Freigburg to Bordeaux). Some connections will be longer by 10-20 km, but faster by 10-20 min. Take those. If not ocasional farming tractors (drugging long queues), average ride is quite fast, withouth anythign too much annoying.

A63: Bordeaux – ES / partially skipping tolls:
Either taking A63 (tw ES) toll-free as far as it goes, or taking tw Arcechone and stopping to climb Dunes du Pyla and then following straight though narrow but not busy at all Western (of A63) roads and get back on A63 from MAGESQ and keeping all the way to ES, passing Irun and San Sebastian. Then exit AP1 toll.

TBA