Re-suggestion, thanks to mastikhor for pointing out the MP.tf stuff!

Sale 1:

https://backpack.tf/profiles/76561198164651434#!/compare/1535328000/1535414400

Looks like 27 keys

Sale 2:

https://backpack.tf/profiles/76561198113107286#!/compare/1535068800/1535155200

https://backpack.tf/profiles/76561198054145550#!/compare/1534723200/1535068800

Sold for Harvest Metal Drill Hat(Can't prove keys were part of trade)

Use there.

Sale 3:

https://backpack.tf/profiles/76561198024883983#!/compare/1532908800/1532995200

https://backpack.tf/profiles/76561198032016356#!/compare/1532908800/1532995200

Sold for PE Sinner Shade

Shade Mini:

https://backpack.tf/suggestion/5b8864ef44325a0415758716

Suggestion for 28 keys.

Sale 4:

https://backpack.tf/profiles/76561198032016356#!/compare/1532908800/1532995200

https://backpack.tf/profiles/76561198089253101#!/compare/1532908800/1532995200

Sold for keys, can't accurately trace.

Sale 5:

https://backpack.tf/profiles/76561198089253101#!/compare/1532995200/1533081600

https://backpack.tf/profiles/76561198116352227#!/compare/1532908800/1532995200

Untrace.

Sale 6:

https://marketplace.tf/items/30071;5;u8

Sold for 64.99 USD

Keys at 1.88 USD

Total is 34.57 keys

Total sales @:

27, 28, 35 keys.

Buyers on MP.tf up to ~29 keys (keys at 1.89)

Taking 35 flat.