Wow, there are a lot of strong opinions about this topic.
I've never even considered making a formal dispute with ebay in the past, and I was hesitant to do so this time, which is why I came to the forum for some advice.
My mentality for requesting a partial refund is that it would cover some of the cost of a repair, hopefully getting the price down to a cost where I can manage it. Really, I just want a lens in sound mechanical condition. I'm equally happy to send it back to her if she thinks my offer is unfair.
If there are people that are willing to pay $200 for it in the condition it's in, then that's great. But I didn't and don't have the idea of profit in mind. I entered into this transaction feeling assure that I would receive a lens in decent condition. There could have been serious haze and deep gouges on the elements and I would not have cared in the least. Obviously if I could afford it, a 250 dollar repair is still worthwhile on this lens. But I would not have bid on this lens if its condition were accurately described. I would have been fully aware that I probably couldn't afford it and left it be.
While most Leica shooters consider a 150 dollar lens to be a good deal, particularly on something like a DR summicron that sells in stores for particularly more, the fact remains that in my position it is a significant sum of money. I gather my money for photography by working hard throughout the summer and saving pennies throughout the school year. I sold off a large portion of my camera gear to be able to afford an M2 and a lens. I was fully aware that this was a risk, but I don't think it's unreasonable to hope that I get gear in reasonable condition in return. My M2 has issues, but I know that I got a pretty good deal on it and old equipment has "personality." More importantly, none of its issues have a real effect on its ability to perform its essential function of taking photos. Nothing was hidden or omitted in the listing, and the seller was very friendly and communicative throughout. I would never have dreamt of contacting that seller with a complaint about the camera.
Furthermore, I've sent her probably close to ten emails since the auction ended, and I've not received a single reply. More recently I tried calling her again with no answer. If a formal claim is the only way to get her attention, then so be it. I would be happy to discuss it with her, but that's obviously not going to work. As it is, she has the option of responding to my claim. I'm willing to work something out with her without pressing paypal arbitration, but I'm pretty fed up with her on all accounts. I call her a deadbeat seller specifically because she has proven herself to be unwilling to communicate with me.
Finally, I started this thread in order to ask some advice about the lens, which I have received. You are more than welcome to think whatever you like about me as a result, but I will politely ask you to refrain from publicly questioning my morals. Feel free to avoid dealing with me in the future if you don't think I'm fair.