I'm 100% with you. I wouldn't trust any vintage electronics off eBay. I did it once, a NOS JVC demodulator. When I got it, it definitely was brand new, but it wouldn't turn on. I had a local stereo shop repair it. They had it for months looking for some kind of relay. I tried it once and got frustrated, put it back in the box. It sits in a closet.If I may offer a bit of an opinion, I think that a big part of the problem you have is EBay. It all seems to wonderful. Tons of glorious equipment all described in glowing terms by sellers. And when it arrives? Rotted out garbage they no doubt found at garage sales. I will never buy anything more complicated than an old SQ decoder on EBay. For me, EBay is good for records, often, but never electronics and never ever vintage electronics. When I need something, I bite the bullet and get it from someone that has already rebuilt it that I trust. It never ceases to amaze me that 'Fabulous, super rare, super desirable Sansui receivers' are always available for a few hundred bucks. And the 'work great' except that only one of four channels has sound, the other three have static, and even that is only in tape monitor and not using the preamp and on and on. Its just not worth the headache. You get what you pay for and caveat emptor and all that crap. But, when it all comes together...BLISS!!!!
In the meantime, I opened my federal stimulus check wallet, bit the bullet, contacted the QRX Restore and bought a fully refurbished Sansui 9001. It's beautiful. CD-4 works perfect. Decoder sounds amazing especially in the synthesize mode. But, it's not without its quirks. Not a day goes by that my heart doesn't skip a beat everytime I turn it on....wondering what could fail on this 47 year old piece of equipment as I flip that switch. (It was already shipped back once due to a problem....I even forget what it was.)
Ebay is best for records. And even at that, sometime "near mint" is a joke. BTW, tip: I found that stuff from an estate sale is usually pretty great. Likely someone's personal stash and treated well. That's what's probably going to happen to all my stuff when I kick it. I have no one to leave it all to.