[FatBoy]

Thanks for all the responses guys. I'm sorry, I realise that my colourful description of the handling is less than precise, but I haven't driven it yet and the owner is inexperienced in the finer points of automotive handling traits.
However, he has said that the roads around where he lives aren't good and that the car behaves badly, even on straight roads.
I'll try to get to drive it myself and hopefully, I'll be able to report back with something a little more useful.
As has already been said, the Billboards will make a bad situation much worse, but I don't necessarily think they are the only problem. My Kirkham drives fine with them on, although if the road surface gets bumpy, they do start to hunt, especially on a trailling throttle or under braking.

Paul