And another.

Sales

Sale 1: Untrace/Bulk

https://backpack.tf/profiles/76561198001673221#!/compare/1592265600/1592352000

https://backpack.tf/profiles/76561198171693323#!/compare/1587686400/1592352000

Sale 2: Sold for DP Citizen's Cane + 2 keys + S.Merc's Muffler (2 keys)

https://backpack.tf/profiles/76561198077730629#!/compare/1591574400/1591660800

https://backpack.tf/profiles/76561198001673221#!/compare/1591574400/1591660800

Using there, as the Cane has fewer sales.

Sale 3: Sold for 17 keys

https://backpack.tf/profiles/76561198868969121#!/compare/1594252800/1594339200

https://backpack.tf/profiles/76561198342161127#!/compare/1594252800/1594339200

Sale 4: Untrace

https://backpack.tf/profiles/76561198197078062#!/compare/1594252800/1594339200

https://backpack.tf/profiles/76561198868969121#!/compare/1594166400/1594252800

Sale 6: Sold for 18 keys

https://backpack.tf/profiles/76561198002757046#!/compare/1593907200/1593993600

https://backpack.tf/profiles/76561198086809084#!/compare/1593820800/1593993600

Sale 7: Untrace

https://backpack.tf/profiles/76561198194454611#!/compare/1591315200/1591660800

https://backpack.tf/profiles/76561198002757046#!/compare/1591228800/1591315200

Sale 8: Sold with 9 keys + 2 refined for PE Virtual Reality Headset

https://backpack.tf/profiles/76561198979423886#!/compare/1597881600/1597968000

https://backpack.tf/profiles/76561198009721889#!/compare/1597622400/1597968000

Probably better used for the Headset.

Sale 9: Sold for 21 keys

https://backpack.tf/profiles/76561198089388084#!/compare/1597795200/1597881600

https://backpack.tf/profiles/76561198979423886#!/compare/1597622400/1597881600

Sale 10: Sold for 19 keys

https://backpack.tf/profiles/76561199041361273#!/compare/1597622400/1597708800

https://backpack.tf/profiles/76561198089388084#!/compare/1597536000/1597622400

Sale 11: Sold for 18 keys

https://backpack.tf/profiles/76561198227334020#!/compare/1597536000/1597622400

https://backpack.tf/profiles/76561199041361273#!/compare/1597536000/1597622400

Sale 12: Sold for 20 keys

https://backpack.tf/profiles/76561198133820283#!/compare/1597449600/1597536000

https://backpack.tf/profiles/76561198227334020#!/compare/1597449600/1597536000

Resold for 18 above.

Sale 13: Sold for 19 keys

https://backpack.tf/profiles/76561198195933333#!/compare/1597449600/1597536000

https://backpack.tf/profiles/76561198133820283#!/compare/1597449600/1597536000

Sale 14: Untrace

https://backpack.tf/profiles/76561198863393935#!/compare/1597536000/1597622400

https://backpack.tf/profiles/76561198195933333#!/compare/1597449600/1597536000

Other exchanges, such as tradebacks, mannco, scrap, qs store, and etc.

https://backpack.tf/item/6064970275

Marketplace

https://marketplace.tf/items/tf2/30874;5;u10

July

$43.56 on July 25 (43.56/1.93 = 23~)

https://manic.tf/keyprice/?at=2020-07-25

https://backpack.tf/item/6577794623

Listings during the time: https://bot.tf/stats/listings/Y5Z36RN3

Classifieds

https://gyazo.com/4e65558e8b4a1754cab5a447477da63a

Buyers are around the 18 key~ mark.

Summary

Sales at 17, 18, 18, 19, 19, 20, and 21.

Marketplace sale at 23.

Conclusion

Excluding 17 as it's under buyers.

While buyers are at around 18, that makes 2 sales at 18, and 1 sale at lower (17) supporting it being in the range.

The 20 key sale did resell for 18, however, both are close enough so I think it's safe to include both here.

23 is probably high as there was a seller at 21 during the time.

Going with 18-21 here.