I was in the same position myself about seven months ago. First time abroad in the MH, on my own. Getting myself into a right state. About six and a half months ago, I wondered what the fuss was all about. Empty roads, unless you’re filthy rich, ignore the autoroutes, set your sat nav to no tolls, except around Rouen, it’s a bit of a nightmare apparently, I wouldn’t know, I used the peage, a couple of euros. I only took the Spanish Portuguese book, and had no problem. In a three month trip, I think I paid less than €50 on sites.
Either take the Aires books, France x2, and the one Spain and Portugal Aires book, or use the Park4night app and you won’t go wrong. If you’re using the app and want to watch tv, make sure you’ve either got plenty of data on your phone or invest in something like the Huawei
mifi unit. Again with a significant amount of data on a 3with legs SIM card. Remember you’ll need a British card to watch British tv.
I would recommend something I found online. “The long road south”, on the outandabout site. The writer gives you almost a turn for turn route card. I found it very handy. All I did was followed it until I got tired, then used P4N for somewhere to spend the night.
Apart from the weather, that’s another story in its self, I had a great time. Doing it all again in February next year.
Go and enjoy your self.