Buying a 10 years old loudspeaker

Its (not "it's"=it is) life expectation is infinite -- within scientific limits of error.

Assuming the speaker has been well treated up till now, that is: check the drive units, their surrounds, the sound (is there homogeneity between the two spkrs); if possible, get someone to check the dc resistance of the drivers, just in case. Regards

Good tips mentioned . I also think you should do a gut check and get a feel of who you are dealing with and the honesty and true info you get from the buyer is real important..Anything can happen down the road,but in most cases a 10 year old speaker ( under normal conditions ) is not a problem.........Simply because the speaker has lasted 10 years has to say something for the quality built in.......

The main issue is if any of the speaker parts have been replaced. If so, was it done by the manufacturer, and are the new parts matched to the old.
Second is if the woofer surrounds are rotting. Rubber surrounds usually last well beyond 10 years. Foam surrounds last around seven. Both types can be replaced.
And yeah, speakers can last a very long time. Plenty of folks still use 40/50 year old speakers.