Nordost Frey-2

I have a 5-meter set of Nordost Frey-2 speaker cables with banana plugs.  It’s 3 years old.  I don’t recall what I paid for it, but I want to know how much I should ask if I decide to list it for sale on AudioGon.  I can find comps for shorter lengths, but not this long.  MusicDirect list price for 3 meters is $3838.  Is there a ratio of used value to new MSRP I should consider?

Lots of questions, I know.  Thank you for any info you can share.

Dan