If you had the proper tools you could replace the bushings in maybe 15-30 minutes per control arm. The front bushings are also kind of a pain in the neck to remove, on my car one side came out pretty easily but I had to fight with the other side for a good hour before I could get the old bushings out. For 'reasonable cost estimate' purposes I'd pay for at least an hours labor with some additional charge for wear-and-tear on the tool. Total cost I'd call reasonable? Maybe $75? There are Chinese aftermarket tools designed to remove and replace W202 control arm bushings for around $180 on fleabay, the real dealer tool is around $650 IIRC.

One thing about having new control arms is that it would really reduce the total time of the repair. I think I could remove and reinstall the control arm in way under an hour per side. Having new arms could reduce the time of repair from an all day affair to a easy half day.

If I was in a hurry or wanted to be 100% sure that the repair would go OK so that I could have the car back in service for a next day commute I'd spring for the new arms. If I didn't have to compete the repair in a day I'd try to replace the bushings myself - it would take longer and be a more difficult repair but you could save at least a couple hundred dollars.

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98 Dodge-Cummins pickup (137K)
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