Yes, at 100K miles, I would expect shocks, bushings and any other suspension wear items to need to be replaced. While parts can be expensive, the real issue is can you afford to do the work yourself?
It may mean borrowing, renting or buying some tools. The dealers, and independants, make the bulk of their money on LABOR. Around me, the going rate is approx $100/hour. So, in the 8hrs or so it may take them to refresh your suspension, realize that about $800-1000 of that will be a labor charge. If you can "DIY" it, that is where the money can be saved. (That said, don't overlook the opportunity cost of DIYing. If you earn $30/hour be sure to charge yourself for the time and effort it takes you to do the job -which likely will take longer than a pro and could leave you without transport until finished). You may realize that the true out of pocket expense for your work is more than you think and a shop (a "good shop" could be worth the expense).
Also, realize your "1998 100k mile car" was once a $40-50K car. Repair costs can be staggering (thank you Porsche
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I tend to be of the "cry a lot once" than "cry a little, very often" when it comes to maintanence and upgrades. Do it right th first time.
The problem of a "progression" rebuild is the need to "redo" things. Replace one component, then another, and when you replace the second one, you may have to redo all the work you did in replacing the first component. Your suspension components all need to work together to be effective. Replacing them all at the same time is more efficient.
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