I asked the seller about that listing. He said he powered it on but that was all the "testing" he did.Wow.. this is a real blast from the past. I was using the 450 Mixer (no tape) in the late 80's for my bedroom studio and stage mixing our gigs. Beautiful piece of gear. I see there's a 460 on eBay now for $300 - that's a nice price even if the recorder section isn't working.
When I see that, I read that as "I tested a bunch of things, and most of them didn't work."