Sale #1: Bought this for 2 keys + 20 ref (~2.45 keys)

https://prnt.sc/vfjbb2 (https://backpack.tf/item/9445636301 - still in fallback)

Other sales:

Marketplace.tf (https://marketplace.tf/items/tf2/5048;6;c6)

Sale #2: $4.25 / $1.79 (https://manic.tf/keyprice/?at=2020-08-19) = 2.37 ~ 2.35 keys

Unknown item history

Sale #3: $4.25 / $1.81 (https://manic.tf/keyprice/?at=2020-08-23) = 2.35 keys

Unknown item history

Sale #4: $4.50 / $1.88 (https://manic.tf/keyprice/?at=2020-09-12) = 2.39 ~ 2.40 keys

Item 1: https://backpack.tf/item/210489278

Sale #5: $14.50/$1.85 (https://manic.tf/keyprice/?at=2020-10-25) = 7.84 ~ 7.85 keys

Unknown item history

All unknown b/o (snapshots not available).

Item tracing:

Item 2: https://backpack.tf/item/205217606

Sale #6: Probably SCM.

https://backpack.tf/profiles/76561198179218222#!/compare/1603152000/1603238400

https://backpack.tf/profiles/76561197966973786#!/compare/1603584000/1603670400

Item 3: https://backpack.tf/item/204380957 (Item history from the one I bought)

Sale #7: untraced

https://backpack.tf/profiles/76561198389307863#!/compare/1601424000/1603756800

https://backpack.tf/profiles/76561198271382917#!/compare/1601856000/1602547200

Item 4: https://backpack.tf/item/198621761

Sale #8: untraced

https://backpack.tf/profiles/76561198203329164#!/compare/1598227200/1598313600

https://backpack.tf/profiles/76561198880178504#!/compare/1592179200/1599696000

Sale #9: SCM

https://backpack.tf/profiles/76561198880178504#!/compare/1601164800/1602288000

https://backpack.tf/profiles/76561198166854369#!/compare/1601337600/1602115200

Item 5: https://backpack.tf/item/198133379

Sale #10: bulk/untraced

https://backpack.tf/profiles/76561198002783030#!/compare/1599955200/1600387200

https://backpack.tf/profiles/76561198983276796#!/compare/1600300800/1601510400

Item 6: https://backpack.tf/item/197325377 (duped)

Sale #11: untraced/missing

https://backpack.tf/profiles/76561197993164506#!/compare/1602374400/1603584000

https://backpack.tf/profiles/76561197993151025#!/compare/1602979200/1604620800

--------------------------

Two selling in the marketplace.tf:

$14.50 / ~$1.81 = 8 keys (https://backpack.tf/item/197813092)

$15.00 / ~$1.81 = 8.29 ~ 8.30 keys (https://backpack.tf/item/202868256)

--------------------------

Valid sales: 2.45, 2.35, 2.35, 2.40, 7.85 keys

Excluding 7.85 keys - an outlier.

Taking 2.35 - 2.45 keys.

lol... I treated this like suggesting an unusual :3