life expectancy of a cdp?


I am looking at a used Parasound cdp. I know that it is based on amount of use , but on average how long should a unit last, and what amount of maintance is required? I read in other threats about the laser having to be serviced in some units.
Gary
garypic
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Back in 1988 I bought a Denon DCD-1500 CD Player. Keep it for about 10 years then gave it to my daughter. She still uses it to this day. Trouble free, never serviced.
My Lexicon has probably close to 10,000 hrs on it and never a lick of trouble.
there is a guy in my building still using and going strong his JVC 1010tn cd player. He told me that he his the original owner.
The Technics cdp I bought in 1986 is still functioning in my son's apartment. The remote did die though.