Fosses Septiques - Chateaubriant area

[Peterh]

After reading all the discussion on this subject we have decided that we should probably upgrade our fosse despite the fact that our French neighbours don't seem inclined to do anything about theirs, which I assume don't comply with the new regulations either. A recent enquiry with one neighbour about whether he would have to upgrade was met with a shrug of the shoulders and the comment "un jour........peut-etre".
Has anyone in the Chateaubriant area installed a fosse recently and if so can you recommend an installer? What can I expect to have to pay for this? The price seem to vary from one area to the next.
Any experiences of fitting one oneself would also be welcomed.
Any information will be gratefully received.
Peter