1) 161 keys

https://mannco.store/item/12221 Sold for $279.99 on September 8, 2022

https://mannco.store/item/440-mann-co-supply-crate-key Keys were at $1.74

$279.99/$1.74= 160.9 keys = ~ 161 keys

I'm not too sure about the item history on Sale 1 as I don't have premium, but if you find it feel free to put it as a reply.

2) Cash trade

Item History: https://backpack.tf/item/12174156311

Seller: https://backpack.tf/profiles/76561198041097718#!/compare/1664496000/1666742400

Buyer: https://backpack.tf/profiles/76561198160856661#!/compare/1664409600/1664841600

3) Incomplete snapshot

Item History: https://backpack.tf/item/1081412556

Seller: https://backpack.tf/profiles/76561197990511314#!/compare/1648598400/1666742400

Buyer: https://backpack.tf/profiles/76561198138503906#!/compare/1645747200/1666742400

4) Cash trade?

Item History: https://backpack.tf/item/1081412556

Seller: https://backpack.tf/profiles/76561198138503906#!/compare/1645747200/1666742400

Buyer: https://backpack.tf/profiles/76561198316071886#!/compare/1666656000/1666742400

Going 161 keys flat.

Feedback is welcome. Thanks!