Hi Jeff, I was recently in an identical situation. I bought a Nak Dragon here on Audiogon, it arrived in perfect cosmetic shape, no obvious damage to the box (like yours, mine was shipped in the original box w/original packing material), but when I tried to open the tape door, nothing. Some latch was obviously not releasing, power was on but no action by the door. I fooled around with it (gently) for a while, jiggling and reaching in to try and find an engaged latch, but couldn't solve the problem. I emailed seller, who originally had said he offered a money back guarantee. The door was working when he packed the deck. Since I decided that I wanted to keep the deck, even if I had to pay for the repair, I did not ask to return it for a full refund. Instead, I took it into a shop that sells and services vintage as well as new gear, and a week later had it back operating perfectly. Diagnosis: the "pressure pad lifter" was missing. Cost: approx $130, which included a cleaning, checking, and head alignment. Don't know how much the pressure pad lifter plus labor alone cost. Don't know what happened to the original pressure pad lifter; fell off in transit? Lost somewhere inside the deck? I assume if the latter, the repair shop would have found it and removed it. Anyway, I asked seller to contribute to the repair cost, which I said I thought fair, and he agreed without argument and shortly thereafter sent me a check for $35. I feel that that was honest and fair and am perfectly satisfied with him, the tape deck, and the way the whole deal went down. My deck was also shipped UPS Ground. Lesson: always double box, even if you pay more to ship. At least you then have a chance of receiving what you paid for.
If I had wanted to return the deck for a full refund, I think that the seller was obligated to accept it, since he had offered that from the beginning. If it had been anything other than a purely (I felt) mechanical problem with the door latch, like a function not working (eg the autoreverse or the autocalibration), I think I would have asked to return the deck, fearing that the cost of repair would be too high. I just felt the latch problem wouldn't be too expensive. $130 was steep, but then it was a vintage piece, not currently manufactured.
If I had wanted to return the deck for a full refund, I think that the seller was obligated to accept it, since he had offered that from the beginning. If it had been anything other than a purely (I felt) mechanical problem with the door latch, like a function not working (eg the autoreverse or the autocalibration), I think I would have asked to return the deck, fearing that the cost of repair would be too high. I just felt the latch problem wouldn't be too expensive. $130 was steep, but then it was a vintage piece, not currently manufactured.