Am I justified in my frustration?

As the title implies, I don't know where I should stand on the issue. I know one thing, I'm mad.

I am mad at myself for not doing more due diligence. I am mad at the seller for not, at first, hearing my concerns and being dismissive of how much of a pain in the *** pulling this rear apart has been. I don't think he thinks its a big deal and goes on to list prices of individual parts prices as if I could just yank those parts of this rearend and turn them the next day.

The title asks a question. It let's you know that I am torn. Is this my own fault? Is it the sellers fault that he used a very liberal definition of "rebuildable"? I do feel duped but I am grounded enough to know that I am ultimately to blame because I trusted.

I do appreciate the seller, in a way, admitting that he misrepresented the part by giving me the $100. It's less than I think is fair but if he felt there was absolutely NO problem with the part then he could have told me to pack sand.

In the end I think he knows he misrepresented the part. He knows what he did. This rear was opened out in the elements for a very long time and he just threw an axle in it and sold it.

It would have been great if he would have said, " Before you buy this I want you to know it was sitting out, opened to the elements for a long time. It might have some issues." NOT "It's a good rebuildable core." I probably would have bought it anyway but I would have not been butt hurt when I found acorns and rat **** and can't get an axle loose after very much work.

I'm not going to all of a sudden think this guy is top notch but I do know I can't call out his name in public because I do hope this is a case of two guys butting heads over one part, as @autoxcuda says.

Sorry, @oldkimmer . I know you were hoping for the name. I just don't have it in me to go that far.