Next..

Sales

Sale 1: Sold for 10 keys

https://backpack.tf/profiles/76561198192602363#!/compare/1599177600/1599350400

https://backpack.tf/item/3012773022

https://bot.tf/stats/listings/Y7939WJK

Sale 2: 40 refined was traced

https://backpack.tf/profiles/76561198112281935#!/compare/1598572800/1598745600

https://backpack.tf/profiles/76561198025336415#!/compare/1598486400/1598745600

Buyout was 9 keys, 40 refined, which was probably the sale, and that rounds to 10 keys regardless.

https://bot.tf/stats/listings/MNRKZN5Q

Another sale for 10 keys

https://bot.tf/stats/item?def=30136&q=5&ef=Miami%20Nights&craft=1&aus=0&ks=0&source=browser_script

https://gyazo.com/8a80f3bb4359b12b070ed50dc64fb765

Other exchanges with mannco, scraptf, tradeit, and marketplace

https://backpack.tf/item/1906216853

Marketplace

https://marketplace.tf/items/tf2/30136;5;u61

July

$18 on July 22 (18/1.94 = 9.28~)

https://manic.tf/keyprice/?at=2020-07-22

September

$22.99 on September 1 (22.99/1.83 = 13~)

https://manic.tf/keyprice/?at=2020-09-01

Listings during the time: https://bot.tf/stats/listings/Y9Q287ZD

22.99 on September 15 (22.99/1.86 = 12~)

https://marketplace.tf/items/tf2/5021;6

https://manic.tf/keyprice/?at=2020-09-15

Listings during the time: https://bot.tf/stats/listings/MLVDX735

Classifieds

https://gyazo.com/b3556e6977c61c6cb447e8e4654e2df8

Summary

Sales at 10, 10, and 10(very likely).

Marketplace sales at 9.5(9.28 rounds to 9.5), 12, and 13.

Conclusion

There were listings at 10 and 11~ during the time of the sale of 13. Going to exclude 13 as a high outlier.

Rounding 9.28 to 9 as the median is above 10, which means rounding to the nearest whole number is necessary.

Going with 9-12 here.