Your sale #1 is kinda outdated even when you posted this suggestion. Shouldn't really be used when there are quite a number of more recent sales.

Sale #2 (i)

With DBD tough stuff muffs now updated at 4.5 buds, this sale is most likely an outlier.

Sale #2 (ii)

-> 1 bud in keys were added along with the steaming villain's veil for the Green Energy Defiant Spartan . http://www.tf2outpost.com/trade/24252109 . From the c/o, this hat was offered on the GE Defiant Spartan. No need to apply overpay

-> This sale is ~3.2 buds.

Sale #3

The seller has a b/o of 3 buds. The sale should be capped at 3 buds.

Current seller

http://www.tf2outpost.com/trade/24376715 b/o 3 buds. (Seems to have sold. Unsure of the content of the trade.)

More sales