Redid this with a whole lot more sales!

Sale 1:

http://www.tf2outpost.com/trade/25321346

Sold for entire bp - total 1495 refined / 17.33 (key price at time of sale) = 86 * 0.9 = 77.4 = 77 keys

Sellers bp before: http://backpack.tf/profiles/76561198081967527?time=1426402800

Sellers bp after: http://backpack.tf/profiles/76561198081967527?time=1426489200

Buyers bp before: http://backpack.tf/profiles/76561198048123031?time=1426230000

Buyers bp after: http://backpack.tf/profiles/76561198048123031?time=1426489200

Sale 2

Sold for 55 keys pure

http://i.imgur.com/yFn6Q2C.jpg

Sale 3

Appears to have sold with a pro aussie ambassador (24) and a bmoc (4) for a scorching guadalalajara (84) = 84 - 24 - 4 = 56 keys

Sellers bp before: http://backpack.tf/profiles/76561198154658453?time=1427094000 (March 23rd)

Sellers bp after: http://backpack.tf/profiles/76561198154658453?time=1427180400 (March 24th)

Sale 4

Sold for duped ge mining light (89) and strange pro festive knife (20) = 98 keys

Sellers bp before: http://backpack.tf/profiles/76561198097962621?time=1425884400 (March 9th)

Sellers bp after: http://backpack.tf/profiles/76561198097962621?time=1426057200 (March 11th)

Sale 5

Sold for pro aussie rocket launcher (72.5) and ~5 keys in sweets = (72.5 + 5) * 0.9 = 70 keys

Buyers bp before: http://backpack.tf/profiles/76561198097962621?time=1425715200 (March 7th)

Buyers bp after: http://backpack.tf/profiles/76561198097962621?time=1425801600 (March 8th)

Sale 6

Sold for spec aussie rocket launcher (60) and ~7 keys in sweets = (60 + 7) * 0.9 = 60 keys

Buyers bp before: http://backpack.tf/profiles/76561198074041436?time=1425628800 (March 6th)

Buyers bp after: http://backpack.tf/profiles/76561198074041436?time=1425715200 (March 7th)

Sale 7

Sold for sunbeams attendant (96) = 96 * 0.9 = 86 keys

Sellers bp before: http://backpack.tf/profiles/76561198108388721?time=1425283200 (March 2nd)

Sellers bp after: http://backpack.tf/profiles/76561198108388721?time=1425369600 (March 3rd)

Sale 8

Sold for duped scorching festive tree (100) = 100 * 0.9 = 90 keys

http://www.tf2outpost.com/trade/25193229

Sellers bp before: http://backpack.tf/profiles/76561198035278233?time=1424937600 (February 26th)

Sellers bp after: http://backpack.tf/profiles/76561198035278233?time=1425024000 (February 27th)

Sale 9

Sold for sunbeams hermes (looked throuhgh all the histories and can't make sense of any of them for a mini so using current price - 97.5) and 6 keys = 93keys

Buyers bp before: http://backpack.tf/profiles/76561197982569301?time=1422604800 (January 30th)

Buyers bp after: http://backpack.tf/profiles/76561197982569301?time=1422864000 (February 2nd)

Sale 10

Sold for 10 buds (11 keys) pure = 110 keys

Sellers bp before: http://backpack.tf/profiles/76561198006886607?time=1425970800 (March 10th)

Sellers bp after: http://backpack.tf/profiles/76561198006886607?time=1426057200 (March 11th)

Mini for pro aussie ambassador:

Average buyer pays ~$60

Average seller receives ~$51

Scm key price ~2.30

60/2.30 = 26 keys

51/2.30 = 22 keys

Range = 22-26 keys

Mini for strange pro festive knife - is duped but i've been told it prob doesn't matter for these kinda items:

Average buyer pays~$50

Average seller receives ~$42.50

Scm key price ~$2.30

50/2.30 = 22 keys

42.50/2.30 = 18 keys

Mini for duped ge mining light:

Lots of confusing/bulk trades plus in/out of a scammer's bp so gonna use current BO of the duped one on outpost - 89 keys

http://www.tf2outpost.com/trade/25697498

Mini for pro aussie rocket launcher:

Average price buyer pays ~$180

Average seller receives ~$153

Scm key price ~$2.30

180/2.30 = 78 keys

153/2.30 = 67 keys

Range = 67-78 keys

Mini for spec aussie rocket launcher:

Average buyer pays ~$150

Average seller receives ~$127.50

Scm key price ~$2.30

150/2.30 = 65 keys

127.50/2.30 = 55 keys

Range = 55-65 keys

Mini for beams attendant:

Sold for ge capo's capper (37-43) pro aussie minigun (36), and a max's (28) = (40 + 36) * 0.9 + 28 = 96 keys

Buyers bp before: http://backpack.tf/profiles/76561198057193344?time=1427439600 (March 27th)

Buyers bp after: http://backpack.tf/profiles/76561198057193344?time=1427698800 (March 30th)

Mini for pro aussie minigun:

Average buyer pays ~$90

Average seller receives ~$76.50

Scm key price ~$2.30

90/2.30 = 39 keys

76.50/2.30 = 33 keys

Range = 33-39 keys

Mini for duped scorching tree:

Sold for 6 buds (12 keys) and 28 keys = 100 keys

http://backpack.tf/profiles/76561198036267748?time=1424851200 (February 25th)

http://backpack.tf/profiles/76561198036267748?time=1424937600 (February 26th)

__________________________________________________________

Ok, so. Sales all over the place, need to narrow this down a bit.

55, 56, 60, 70, 77, 86, 90, 93, 98, 110

Outpost research

http://www.tf2outpost.com/trade/25477903 - duped one

Entire bp minus a few items ~1500 refined = 1500/17 = 88 keys

4.2 buds ~45 keys

http://www.tf2outpost.com/trade/25619440 - lots of good offers but his BO is 90 and it hasn't sold at that, he's put up more recent trades with lower buy out and still unsold

Clean Aces high KE (outdated) + S.Professional shotgun, Professional baby face kit and a Professional Collectors fan o war >100ish

Statrak M9 Bayonet Vanilla ~86 keys

flaming lantern bonk boy (outdated, has BOs around 120 on outpost) ~120

vivid plasma modest ~85 keys

http://www.tf2outpost.com/trade/25587284

hellfire armored authority ~ 65 keys

aces high ke again (OUTDATED) ~100 keys

mallard samur-eye

Chicoptera Venata Familiar Fez (OUTDATED) and Aussie Ambassador with Spec. KS ~100 keys

circling heart noble nickel + 5 keys

http://www.tf2outpost.com/trade/25395226

scorching whoopee ~70 keys

67 keys + 19 ref + Strange Festive Huntsman ~ 75 keys

Offers seem to indicate that the sales below 80 were quicksells, so discounting those. Some higher offers but a lot were hats that are also outdated and I haven't done minis for each one. Going with 86-110 for the range.

(thanks zapperz and mindacos for advice)