It’s a really relaxed place so you should be fine in your van. There was a camper and a couple of tents there when we were there. We would have stayed there ourselves but we didn’t realise it was there until the next day as although it’s just round the corner from the main square/bike wash it’s not visible and not signed.
It is possible to drive up to the higher lift station and theres plenty of really quiet places to stay up there, but it is designated as a nature reserve so we turned back. Same goes for the track from the car park. It takes you into a reserve. So maybe best avoided.
There wasnt a lot of info/signs about the Mtb’n so we struggled a bit at first. But the guy who runs the photo hut is english and was really helpful.
Yes bike wash is definitely an option for hose down.
My friend used the toilets in a cafe on the square and they were very friendly by all accounts.
Would love to go back. Great trails.
If you’re taking the Frejus tunnel in the van be warned its really expensive