I'm just reposting my previous suggestion.

Many people complaining about the range (1-2 keys)

Now i'm trying a 1-1.5 keys range to make the price change more progressive.

Sellers

[url]http://backpack.tf/classifieds/search/heavies[/url] 1 key

[url]http://bazaar.tf/trade/188081[/url]: 1 key

[url]http://www.tf2outpost.com/trade/9478379[/url] 1 key+ 1ref: Sold out

[url]http://www.tf2outpost.com/trade/9477351[/url]: 1 key+ 3ref: Out of stock, sold one 2 weeks ago.

[url]http://www.tf2outpost.com/trade/8698586[/url] 2 keys: Sold at least 2 [¤¤¤¤Yellow Drug¤¤¤¤ and -=GHS=-Wyran]

[url]http://www.tf2outpost.com/trade/3538423[/url] 2 keys: Sold at least 2 [th3davinci[BXP40] and Starship ☭], rejected an offer of 6 ref

[url]http://www.tf2outpost.com/trade/9048268[/url] 2 keys: rejected 1 key offer

[url]http://www.tf2outpost.com/trade/8957990[/url] 2 keys: Many buyers

[url]http://www.tf2outpost.com/trade/9941179[/url] Offer of 1 key+ 1ref

[url]http://www.tf2outpost.com/trade/6809756[/url] 3 keys: rejected 1 key offer

[url]http://www.tf2outpost.com/trade/9314009[/url] 2 keys: rejected 1,5 keys offer

[url]http://www.tf2outpost.com/trade/9504910[/url] 10 ref: rejected 7 ref

Buyers

[url]http://www.tf2outpost.com/trade/9476925[/url] Buy one for 4.66 ref. (Reseller, so this is the cheapest price he can offer to get one)

Others buyers are usual lowballers, and they can't buy for their price (2 ref to 3.66 ref):

[url]http://www.tf2outpost.com/trade/9192645[/url]

[url]http://www.tf2outpost.com/trade/9729691[/url]

[url]http://www.tf2outpost.com/trade/9950615[/url]

Finally it's still possible to get that strange for 1 key, but many sellers are successful with a price of 2 keys, even rejecting offers of 1.5 keys.