This price is settling, in between 2.66 ref and a key. It’s rare to find a seller selling for 2.33, far too rare for it to be included in the official range, in my opinion. I could only find one on outpost, and people have been adding him, even after he sold it, to try and get it for this price.

http://www.tf2outpost.com/trade/6614470 - Sold for 2.33

In my opinion this demonstrates that this is a quick sell price that people really want to find so that they can get it for the cheapest possible amount. Outpost has wised up to this, and everyone is selling for either 2.66 ref or a key. And for every trade like this, there are those that overprice for profit:

http://www.tf2outpost.com/trade/6403375 - Sold for 3 ref

This is why it is necessary to narrow the range. Here are some that have gone through for a key:

http://www.tf2outpost.com/trade/5398232 - Sold for Marxman (1 key)

http://www.tf2outpost.com/trade/6529525 - Sold for 1 key

http://www.tf2outpost.com/trade/6590210 - Sold for 1 key

http://www.tf2outpost.com/trade/6314177 - Sold for 1 key (another offer of 2.66, but took the key)

http://www.tf2outpost.com/trade/5147220 - Sold for 1 key

And some at 2.66:

http://www.tf2outpost.com/trade/6202908 - Sold for 2.66 (later offer of 1 key)

http://www.tf2outpost.com/trade/6344935 - Sold for 2.66

http://www.tf2outpost.com/trade/6488383 - Sold for 2.66

This illustrates that the common market price is either a key, or just below. And before anyone asks, I think that the true price of keys is 2.77 – 2.88, and this is why a key is translated to 2.88.

Let me know what you think.