Resuggesting this with more sales.

Sale 1

Sold for aussie black box (19 keys) and ambassador (15-16 keys) and bills hat (2.5 keys) - 37 keys * 0.9 = 33 keys

Sellers bp before: http://backpack.tf/profiles/76561198037956864?time=1427007600

Sellers bp after: http://backpack.tf/profiles/76561198037956864?time=1427266800

Sale 2:

Sold for planets villain's veil 39-44 = 41.5 * 0.9 = 37 keys

Buyers bp before: http://backpack.tf/profiles/76561198110993295?time=1427353200

Buyers bp after: http://backpack.tf/profiles/76561198110993295?time=1427439600

Sale 3:

Sold for circling heart desert marauder 36-40 keys= 38 * 0.9 = 34 keys

Sellers bp before: http://backpack.tf/profiles/76561198110993295?time=1427439600

Sellers bp after: http://backpack.tf/profiles/76561198110993295?time=1427526000

Sale 4:

Sold for circling tf logo master's yellow belt 45 keys = 45 * 0.9 = 41 keys

Sellers bp before: http://backpack.tf/profiles/76561198047433991?time=1426921200

Sellers bp after: http://backpack.tf/profiles/76561198047433991?time=1427007600

Sale 5 (credit to 《◎】Telepathic【◎》) - this one is duped, but doesn't affect the range either way

Sold for 4 buds (~8 keys each at time of sale) and 6 keys = 38 keys

http://i.imgur.com/zhDPvtS.jpg?1

http://i.imgur.com/UwLlu7F.jpg

Sale 6

Sold for molten mallard noble = 43 * 0.9 = 39 keys

Sellers bp before: http://backpack.tf/profiles/76561197996095002?time=1428303600 (April 6th)

Sellers bp after: http://backpack.tf/profiles/76561197996095002?time=1428649200 (April 10th)

Sale 7

Sold for amaranthine human cannonball = 71 * 0.9 = 64 keys

Sellers bp before: http://backpack.tf/profiles/76561198065741250?time=1428822000 (April 12th)

Sellers bp after: http://backpack.tf/profiles/76561198065741250?time=1428994800 (April 14th)

Sale 8

Sold for kill-a-watt brotherhood of arms (47-63) = 55 * 0.9 = 50 keys

Sellers bp before: http://backpack.tf/profiles/76561198055544256?time=1428735600 (April 11th)

Sellers bp after: http://backpack.tf/profiles/76561198055544256?time=1428822000 (April 12th)

Sale 9

Sold for morning glory soldier's slope scopers (65-73) = 69 * 0.9 = 62 keys

Sellers bp before: http://backpack.tf/profiles/76561198071647163?time=1429081200 (April 15th)

Sellers bp after: http://backpack.tf/profiles/76561198071647163?time=1429167600 (April 16th)

Mini for tf logo yellow belt:

Traded with stormy killer kabuto (37-44 keys) for cauldron bubbles tossle (86) = 86 - 41 = 45 keys

Sellers bp before: http://backpack.tf/profiles/76561198055256133?time=1426748400

Sellers bp after: http://backpack.tf/profiles/76561198055256133?time=1428774022

Mini (for my mini) for cauldron bubbles tossle:

Sold/offered with stormy tossle (25-32), nuts n bolts tossle (20-24) and steaming tossle (19-23) for beams tossle (142-150) = 147 - 18.5 - 22 - 21 = 86 keys

Sellers bp before: http://backpack.tf/profiles/76561198041843269?time=1425283200

Sellers bp after: http://backpack.tf/profiles/76561198041843269?time=1425628800

Mini for mallard noble:

Sold for peace sign detective noir (15-20) and max's (27) = (17.5 * 0.9) + 27 = 43 keys

Sellers bp before: http://backpack.tf/profiles/76561198025506314?time=1428649200 (April 10th)

Sellers bp after: http://backpack.tf/profiles/76561198025506314?time=1429081200 (April 15th)

Mini for kill-a-watt boa:

http://backpack.tf/vote/id/55304685b88d8836378b5f4c

From past listings on outpost, offers show lower end is more where the market is.

http://www.tf2outpost.com/trade/25027277

3.3 buds pure (buds were ~10 keys)

max's head (~30 keys at the time)

Offers suggest high end sales are outliers, setting range around the lower sales.