I do not know to much about the suspension, so here goes...

 

Do I need any extra parts with a coilover set? Like camber arms and so on??

If you are lowering the car then yes you will need adjustable other bits to correct the camber etc...

 

HTH :)

Well with the coilovers you can adjust the height to your desired position and they can be adjusted to stock height which means theres no need for camber arms BUT if your setting up for a lowered height which require more than 1 degree adjustment then its recommended that you buy the lot, as the camber angles will be far too negative for road use and cause premature tyre wear, (front/rear camber arms and front tension rods), after that its up to you how far you go.... poly bushings struts roll bars etc etc.

A good set of front and rear camber arms should set you back about £300 tension rods £150 add that to your coilover cost.

Yep what he said

 

It would be a good plan to go for a ride in a car running on coilovers they are alot stiffer and will come as a big and not necessarily good surprise if your used to runnning on standard suspension