Auto Parts: Volvo parts, rule of thumb, future thanks

Question
Right now I'm looking for an alternator but, I'm also wondering about other parts for the future.
Thanks
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I have a 1988 240dl volvo and I'm having trouble finding used parts for it. I'm wondering what other years and models of Volvos have compatible parts?
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what kind of parts are you looking for?

Answer
if you are looking for parts that are common wear items i would not go with used. chances are they are in the same condition as your old ones. however the best rule of thumb is to go with a year that is one newer or older. any more than that and you run into changes.