I was going to say offer $60 to $70 and see what he says.
If seller looks on eBay they'll ask for a lot more. But then some people don't want to deal with the hassle of selling online, shipping, etc. Craigslist is still good for local sales, I also sell a lot of surplus electronics equipment on Facebook Marketplace.
TL;DR. Its "real worth" is still going to be what's in it, and how much a collector is willing to pay. Hope it doesn't go to a hoarder!
