To me (IMO): bin is a fixed price and thats that.
Offers with a bin mentioned means offer less than bin.
In this case I was just being lazy - offer came up just before I started looking for a related script, so I thought I'd take it. Without, it just men't - a few searches on G. So I'm not bothered, nor want to play games about it.
That being said, I think any bin should be a fixed price - as in the case of this I would not have made an offer, if no bin was stated. As I was only looking for a quick solution. But every time things like this happen, it puts me off buying on/from forums, unless I know the people involved or the value of purchase is worth the research.
90% of my lower end buying is to save time, not to start a ping pong game of PM's. Which tends to go on and on. Hence would only look at bin and not offers, which can return a counter offer (in which time another solution turns up).