I'm off to Font in October around the 8th to the 22nd and looking to see if anyone is interested in sharing the costs. I've a couple of spaces free in my van plus pads and can do a drop off wherever is convenient once in the forest.
I've just checked the ferry people and it looks like it will cost around £36/40 depending on timing. The diesel was around £150 last time I went over (Feb).
I'm based in Sheffield, so a pick up from here or somewhere en-route to the ferry would be preferred.
Drop me a PM if you want any more details
Cheers