for my E320, about 1 hour's time, get both wheels off the ground, using jackstands. check your owners manual as to where to put the stands.
once wheels are off the car, you will see the c-shaped sway bar brackets holding it and its rubber bushings, to the front of the control arms and where it is also mounted to the subframe on both sides.
standard ratchet and socket is all you need. plus some silicon grease to help you get the bushings off and on the bar.
4 bushings=approx $30
1995 MB E320 Wagon
2001 BMW 530i
2007 MINI Cooper S (!)