Let's see
Audiogon has 326 listings (new & used ) to browse - take a look for used
USAudiomart has ads for 293 RCA cables and 192 XLR interconnects
UsedCable.com 131
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Why aren’t there many used cables on the market?
We know good cables are extremely expensive and used cables would seem a good thing to buy.
My dealer never has used cables and also conveyed to me that the more expensive cables carry profit margin of 80%.
So $5000 cables yield a.profit for both manufacturing dealer by $4000. Was stated that these cables arent bought very often. Mostly the cheaper cables between 400 and 900 are purchased.
Obviously not a lot of money selling used cables and I think manufacturers may not allow their dealers to sell used cables.