Dino Dance. It's like Crab Rave but better.

https://backpack.tf/item/6396687802

Sale 1) Sold for $350 when Keys were ~$1.79 each

https://marketplace.tf/items/30704;5;u100

https://marketplace.tf/items/5021;6/Mann%20Co.%20Supply%20Crate%20Key

350 / 1.79 = 195.53, which I'll round to 195 Keys

https://backpack.tf/item/6947809370

Sale 2) ?

https://backpack.tf/profiles/76561198247218246#!/compare/1538611200/1538697600

https://backpack.tf/profiles/76561198165114206#!/compare/1538524800/1538697600

https://backpack.tf/item/7245903251

Sale 3) Sold for 155 Keys

https://backpack.tf/profiles/76561198003724587#!/compare/1540944000/1541030400

https://backpack.tf/profiles/76561198036445124#!/compare/1540944000/1541030400

Counting this as low because it's close to a Buyer at 150 Keys -> https://imgur.com/a/hoGnG4p

https://backpack.tf/u/76561198036445124 - The Buyer

Sale 4) Sold for a Sunbeams Backwards Ballcap (140 Keys) + Blizzardy Storm Bonk Boy (46 Keys)

https://backpack.tf/profiles/76561198036445124#!/compare/1542672000/1542758400

140 + 46 = 186 Keys

Ballcap Mini

https://backpack.tf/suggestion/5c2a6815cf6c7557d6000a17 - 140 Keys

Bonk Boy Mini

https://backpack.tf/suggestion/5c29b940cf6c752724723638 - 46 Keys

Sale 5) Sold for 72 Keys + Factory New Cool Blue Mew Pistol + Strange Field-Tested Pro KS Fire Glazed Sniper Rifle

https://backpack.tf/profiles/76561198424469290#!/compare/1544227200/1544400000

There's no Mini for the Pistol.

Sale 6) Quicksold for 150 Keys

https://backpack.tf/profiles/76561198113188320#!/compare/1544313600/1544400000

Sale 7) Given to a broker

https://backpack.tf/profiles/76561198070705963#!/compare/1545264000/1545350400

https://backpack.tf/profiles/76561198218628708#!/compare/1545177600/1545264000

Sale 8) Sold for a Green Energy Prehistoric Pullover (184 Keys) + ~27 Keys of Items + 3 Keys

https://backpack.tf/profiles/76561198218628708#!/compare/1545436800/1545523200

184 + 27 + 3 = 214, which I'll round to 215 Keys

https://backpack.tf/item/7156428766

Sale 9) Sold for 86 Keys + Smissmas Caribou (85.5 Keys) + Blizzardy Storm Large Luchadore (15.5 Keys)

https://backpack.tf/profiles/76561198301015840#!/compare/1538524800/1538697600

https://backpack.tf/profiles/76561198036070209#!/compare/1538611200/1538697600

86 + 85.5 + 15.5 = 187, which I'll round to 185 Keys

Caribou Mini

https://backpack.tf/suggestion/5c2a45d444325a361d3f638f - 85.5 Keys

Luchadore Mini

https://backpack.tf/profiles/76561198192602363#!/compare/1545782400/1545868800 - 2 sold for 16 Keys each

https://backpack.tf/profiles/76561198061275415#!/compare/1545264000/1545350400 - Sold for 16 Keys

https://backpack.tf/profiles/76561198254802111#!/compare/1545955200/1546041600 - Sold for 15 Keys

https://backpack.tf/profiles/76561198255764866#!/compare/1542412800/1542585600 - Sold for 14 Keys + 8 Refined

https://marketplace.tf/items/380;5;u30 - Sales at 16, 17, and 18 Keys

Taking 15 - 16, since there is a Seller at 15 Keys and a Buyer at 14 Keys: https://imgur.com/a/aJ6lX7O

https://backpack.tf/item/1385899830

https://backpack.tf/u/76561198192602363