Why not have it done elsewhere the DPF can be purchased for under 200ukps and is a quite easy job to change, at 140000 miles it will be pretty sooted up.The eloy fluid is very expensive but can be purchased at a number of outlets the only problem is turning the light out this requires the Citroen computer I forget the name although they are identical mechanics Peugeot use a different computer interface program named Planet as do Ford.