Quoted from flynnibus:Negotiating via email/PM when you've never seen the game in the first place usually ends up poorly.
If you want to haggle... get a live conversation going.
Totally agree- low balling or throwing numbers at the seller does not equal negotiating. Your offer was probably insulting to the seller, thus deserved no response. To negotiate, you need facts to back up your offer (comps etc). If someone low balls me, I might even respond with a price just above what I was asking. They're the one that threw out the original price.. Ask questions, get more pictures, find a reason to negotiate. Its not just a matter of trying to find out "what they will take".