hi i wonder if anybody could help me?my fiesta(work horse)has recently started making a clunking noise when driving over potholes or speed bumps,ive been advised that it is the bushes and was just wondering if anybody knows the best and cheapest place to supply and fit them?thanks in advance.

Can't help but send th ebill to the council!

And why would that be, he says when he drives over a pothole it knocks, that would suggest a problem with lower arm, as the op says bush, or ball joint.
Its not just pot holes that it would knock on, no doubt if he drove over a speed bump, it would knock.

I drive over pot holes all day and night, very hard to avoid them the state the roads are in, and its not damaged my car.

Lower arm bushes or ball joints do just fail, ball joints all it takes is a little split in rubber, water gets in and and mixes with grease washes grease out and the ball joint is goosed, and the ball joint just rattles around in it seating. = knocking.

Easier to change the full wishbone as the ball joint is riveted on.

Labour is around 1 hour each for these, however more cost effective to do both and get the tracking done aswell.

100% agree.