rear strut noise?

In my moms 97 tracer when going over bumps the back left of the car clunks around. someone told me just by glancing at it that the strut is probably bad. isn't this an expensive fix? what can happen if it isn't done right away due to $$$??? Safety hazard is my biggest concern. Thanks!

Not really a safety hazard.
If you replace just the one strut you are looking at maybe $100-150 parts and labor. Chances are though that if one is bad, the others are either bad or likely to go soon. I think you can usually get the set for all four wheels for somewhere around $100... something like buy 3 get 1 free. I seem to remember seeing that advertised at Pep Boys.
Anyway... not an emergency. You just might have a louder and slightly bumpy ride til you fix it.

ours had a clunking noise in the back, and when I finally looked closely - I saw a broken coil spring, and a rusty strut shaft were it should have been shiny chrome. It was that way for a couple of years before I replaced it as part of redoing the rear brakes. Other than the clunking noise being gone - there didnt seem to be any other difference. I didnt replace the strut on the other side, as it was not rusted and its spring wasnt broken. The car has 200k miles on it, so I am assuming the shock-absorber feature of the struts is long dead - but it handles well enough.

yes fords cars are known for broken rear spring you will need a spring compressor to do this. if you know anyone with a shop they might do this for you.