Short answer: you might not have missed much.
Sorry you didn't get an answer earlier, but here are some pointers if you're after a deck in future.
Assuming you don't own a tape deck and haven't owned one before, you'd be opening yourself to a certain amount of pain and cost. I'd hasten to add that I think it's the good kind of pain and the good kind of cost, but the first thing you must accept with open reel tape is that it's for most practical purposes a dead format. I think only one manufacturer of blank tape remains (RMGI, formerly of the Netherlands, and now, I believe, of France).
A tape deck will be a bargain only if it's in playable or easily repairable condition. In many cases, you won't even be able to get parts if something is wrong with it. The first thing to look at would be the condition of the heads. If they're dirty, that's not much of an issue, but corroded, badly worn, or cracked are all things you need to look out for, as they would essentially render the deck useless.
Make sure also that the spindles are complete and undamaged. Damage such as a bent spindle may indicate that the deck has been knocked onto its front at some point.
Also look at the pinch roller(s). Dried out is a problem, although it is still possible to buy replacements (at a cost though).
If you do get a deck that works well, they're a joy to use and there's something about tape is like no other format. It's even rewarding to record CDs and play them back as open-reel tape. But I do think you need to inform yourself about the issues, because there are many. There's quite good information available at a number of websites, and the Tapeheads forum is one to join if you haven't done it yet. There are also a lot of Youtube videos of working decks if you want to check what a particular model you are interested looks like in operation.
Remember that the problem with "bargain" decks is that unless you know what to look for, you can be letting yourself in for multiple times the cost of the deck just to get it back into working order. It tends to be better to spend a few hundred dollars on a properly working deck than grab a bargain and hope to get it rolling some day. You also have to be careful about spending more though: it's no guarantee. Check the tape page at eBay for more on that.
Hope this is some help....