Lee if its a clio II you need 4 springs, the guy you spoke to probably thought it was a Clio I. If its a Clio III this has similar setup to clio II, you still need 4 springs.
To confuse things more people in the trade confuse trailing arm with springs to a torsion beam, sometimes a trailing arm is reffered to as a torsion beam but the whole point of a torsion beam is to have no springs to save space.