Infrequent use Poid Lourds tax

[pigiron]

I have heard that there is a French road tax scheme trucks which are used infrequently such as horse boxes and race car transporters which are maybe used once or twice a month.

I picked this information during a rather boozy awards ceremony after a race meeting.....as I think I remember you have to notify the prefecture in advance of each trip, a bit like pay as you go???

In the UK the equivalent is that you may tax an HGV as a private vehicle (large car rate) providing it is not used for profit or reward.

Any ideas?

Also does any one know what it costs to tax a 7.5 tonner here.