Sale 1:

Sold for 4 keys

https://backpack.tf/profiles/76561198054945991#!/compare/1706054400/1706140800

https://backpack.tf/profiles/76561199059545121#!/compare/1706140800/1707004800

https://backpack.tf/item/7759240314

= 4 keys

Sale 2:

Sold for 4 keys

https://backpack.tf/profiles/76561199107865875#!/compare/1705276800/1705363200

https://backpack.tf/profiles/76561198350267590#!/compare/1705276800/1705363200

https://gladiator.tf/sales?item=Screaming%20Tiger%20Taunt:%20The%20Balloonibouncer&at=2024-01-17T06:25:39.608Z - gladiator confirms

https://backpack.tf/item/4953375482

= 4 keys

Sale 3:

Sold to a bot for 3 keys + 61.44 ref?

https://backpack.tf/profiles/76561198113084770#!/compare/1705795200/1705881600

https://backpack.tf/profiles/76561199111292616#!/compare/1705881600/1705968000

https://gladiator.tf/sales?item=Screaming%20Tiger%20Taunt:%20The%20Balloonibouncer&at=2024-01-23T06:53:55.366Z - labelled as 3 keys + 64.44 ref, close enough

https://backpack.tf/item/4953240424

= 4 keys

Sale 4:

Sold to a bot with 6 ref for 4 keys

https://backpack.tf/profiles/76561198168578115#!/compare/1704931200/1705017600

https://backpack.tf/profiles/76561199125108615#!/compare/1704931200/1705017600

https://gladiator.tf/sales?item=Screaming%20Tiger%20Taunt:%20The%20Balloonibouncer&at=2024-01-13T06:25:39.608Z - labelled as 3 keys + 56.88 ref

https://backpack.tf/item/9589251063

= 3.9 keys

Other Sales:

#1

https://backpack.tf/profiles/76561199112522018#!/compare/1705449600/1705536000

https://backpack.tf/profiles/76561199177136435#!/compare/1705363200/1705536000

https://gladiator.tf/sales?item=Screaming%20Tiger%20Taunt:%20The%20Balloonibouncer&at=2024-01-18T06:21:03.750Z - labelled as 3 keys + 63.88 ref (~4 keys)

https://backpack.tf/item/12390367078

Untraceable

#2

https://backpack.tf/profiles/76561199177136435#!/compare/1705363200/1705536000

https://backpack.tf/profiles/76561199128560410#!/compare/1705449600/1705536000

https://gladiator.tf/sales?item=Screaming%20Tiger%20Taunt:%20The%20Balloonibouncer&at=2024-01-18T06:21:03.750Z - labelled as 3 keys + 63.88 ref (~4 keys)

https://backpack.tf/item/12390367078

Untraceable

#3

https://backpack.tf/profiles/76561199125108615#!/compare/1705363200/1705449600

https://backpack.tf/profiles/76561198043444428#!/compare/1705449600/1705536000

https://backpack.tf/profiles/76561199139085248#!/compare/1705449600/1705536000

https://gladiator.tf/sales?item=Screaming%20Tiger%20Taunt:%20The%20Balloonibouncer&at=2024-01-19T06:25:39.608Z - labelled as 3 keys + 63.88 ref (~4 keys)

https://backpack.tf/item/9589251063

Untraceable

#4

https://backpack.tf/profiles/76561198731436153#!/compare/1708041600/1708128000

https://backpack.tf/profiles/76561199110809353#!/compare/1708041600/1708128000

https://backpack.tf/item/7983878171

Bulk for Aussie RL

#5

https://backpack.tf/profiles/76561199021293457#!/compare/1704240000/1704758400

https://backpack.tf/profiles/76561198981867692#!/compare/1699488000/1706054400

https://backpack.tf/item/6118018427

Untraceable

#6

https://backpack.tf/profiles/76561199118190771#!/compare/1706486400/1706572800

https://backpack.tf/profiles/76561199084784906#!/compare/1706400000/1706486400

https://backpack.tf/item/4980242704

Untraceable, probably bulk for keys

#7

https://backpack.tf/profiles/76561199084784906#!/compare/1707264000/1707350400

https://backpack.tf/profiles/76561198348930769#!/compare/1707264000/1707523200

https://backpack.tf/item/4980242704

Untraceable, 3 keys match

#8

https://backpack.tf/profiles/76561198125791160#!/compare/1705104000/1705190400

https://backpack.tf/profiles/76561199128560410#!/compare/1705104000/1705190400

https://gladiator.tf/sales?item=Screaming%20Tiger%20Taunt:%20The%20Balloonibouncer&at=2024-01-15T06:25:39.608Z - labelled as 3 keys + 60.66 ref (~3.95 keys)

https://backpack.tf/item/4955458746

Untraceable

#9

https://backpack.tf/profiles/76561199140491352#!/compare/1697068800/1705881600

https://backpack.tf/profiles/76561198113084770#!/compare/1705795200/1705881600

https://backpack.tf/item/4953240424

Bulk for Cloud 9 Highway Star

https://backpack.tf/item/4960466968 - marketplace

Sellers:

https://imgur.com/a/KucNkSP

https://backpack.tf/item/9282728156 - ~4.05 keys

https://backpack.tf/item/9589251063 - ~4.05 keys

https://backpack.tf/item/5819845698 - ~4.1 keys

https://backpack.tf/item/4953240424 - marketplace

https://backpack.tf/item/4960466968 - marketplace

https://backpack.tf/item/12390367078 - marketplace

https://backpack.tf/item/11401728767 - marketplace

https://backpack.tf/item/5010984132 - marketplace

https://backpack.tf/item/4955458746 - marketplace

Sales at:

3.9

4 (3x)

3.9 is supported by the untraceable gladiator sales (#8).

Taking 3.9-4.