Meh, I guess I fall somewhere in the middle...I'm not a pushover and like to do my research and feel like I know what is fair but I don't want to come across as unreasonable either so I am willing to give a little to try to reach an agreement where both parties feel they were treated fairly.
I get really turned off by some attitudes I see in negotiating with the "get all you can get" mentality.
I hate confrontation...so I'm bad at it. I can barter a little bit for sales/purchases of used items but don't do it much. If the item is a good deal, I don't bother bartering. There's a point where it's just an insult.
I hate confrontation as well. I guess that would make me a crappy negotiator I do sometimes make a reasonable offer on a used item that I am looking to buy. I recently bought a used dresser for the new baby - guy was asking $70, I said would you take $60, he said yes.....LOL. I wouldn't haggle with someone over things like that though. I always hated working in customer service and some people just try and get EVERYTHING for a deal, always asking you to throw stuff in for free.....ugh.
I usually get the things that I want, but mostly because I get mad to the point of screaming (if it is something major like how my car broke down less than two weeks after driving it off the lot) and people give me what I want. As far as regular purchases, I shop around until I find the right price for what I want I will try to get them to move a bit but generally I don't mind paying the asking price if the item is in decent condition, I tend to think of people selling things used in a tough spot and needing the money (which is silly of me but we have been there before) so I don't try to haggle too much.