All sorts of unexpected here.

Added 1 Key for a Green Energy Buckaroos Hat(24.5 Keys, rounding to 25)(24 Keys total)

http://backpack.tf/profiles/76561198129876495#!/compare/1465084800/1465171200

http://backpack.tf/profiles/76561198054139011#!/compare/1465084800/1465171200

Sold with a #45 Bone Dome(2 Keys) and 1 Key for an Eerie Orbiting Fire Scotch Bonnet(29.5 Keys, rounding to 30)(27 Keys total)(Credits to Randy for the sale)

http://backpack.tf/profiles/76561198139668780#!/compare/1464652800/1464739200

Sold with ~1 Key in Sweets for an Australium Pro KS Minigun(~29 Keys)(28 Keys total)

http://backpack.tf/profiles/76561198095285934#!/compare/1463875200/1464134400

Sold for a Corona Australis(15 Keys at the time) and a Strange Pro KS Machina(~13 Keys)(28 Keys total)

http://backpack.tf/profiles/76561198166081596#!/compare/1457856000/1457938800

Sold for a Blizzardy Storm Le Party Phantom(26 Keys) and 4 Keys(30 Keys total)

http://backpack.tf/profiles/76561198066788252#!/compare/1462320000/1462752000

#45 Bone Dome mini suggestion

Sold for ~2 Keys in items(at the time)

http://backpack.tf/profiles/76561197993198149#!/compare/1462233600/1462492800

Using 2.

Sales seem to fit, 24-30 Keys should be fine.

Additional Proof/Counter-Proof/Constructive Criticism/Feedback is always appreciated.