The architect actually said I would use a hussier to look at my walls and take extensive photos, then look at my neighbours' (the shared walls - it's a town house), and take photos of theirs. If any issues arise during the construction process - cracks they say suddenly appeared in their shared wall, for example, which they blame on my renovation, the hussier has provided an official report which lays out the status quo beforehand.
It's something I was planning to do myself with my neighbours anyway, but apparently the hussier provides the legal statement/report. Some hussiers we have spoken to don't provide this service, but we have spoken to one in Carcassonne who has done several of them.
Nick, I'll ask the architect if there's any difference between that and the referer preventive - perhaps the hussiers have added a bit of moonlighting to their portfolios :)
Tracy, I'm renovating a ruin from top to bottom, on a small budget (so far). The builder I'm talking to is not a SARL, but an AE, and tells me that he's been quoted 5000 euros p.a. for the insurance, and that AE artisans have a limit of 36,000 p.a. that they can earn before changing to a SARL. He reckons it does not make it worthwhile therefore to cough up 5000 p.a. as an artisan.
I'm a bit out of my depth with this and paddling away beneath the waves - on the one hand I want to be covered, and the workers safe, on the other if I bring in a SARL, it will probably cost me 2-3 times as much, and as a result not much work will get done! I guess this is the sort of dilemma that most renovators have to look at at some stage in France.
I think I'm going to have to shop around some more - dear God, more devis....If anyone has some recommendations for a suitably insuranced builder in the Limoux/Carcassonne and surrounding areas, I'd love to hear them.
Thanks all, for your contributions, and for caring.