Sale 1:

Sold with 8 keys for Scorching Big Country (Mini at 70 below)

No (recent) Outpost trade

Seller: https://backpack.tf/profiles/76561198053767371#!/compare/1510531200/1510704000

Buyer: https://backpack.tf/profiles/76561198086070401#!/compare/1510444800/1510531200

X = 62

Sale 2:

Sold for 50 keys

Seller: https://backpack.tf/profiles/76561198066507816#!/compare/1510444800/1510531200

Buyer: https://backpack.tf/profiles/76561198116230594#!/compare/1510444800/1510531200

X = 50

Sale 3:

Sold for 45 keys

Seller: https://backpack.tf/profiles/76561198123441069#!/compare/1510272000/1510358400

Buyer: https://backpack.tf/profiles/76561198200973421#!/compare/1510272000/1510358400

X = 45

Sale 4:

Sold for 38 keys ~1 day after becoming tradeable

Seller: https://backpack.tf/profiles/76561198080179568#!/compare/1510012800/1510099200

Buyer: https://backpack.tf/profiles/76561198123441069#!/compare/1510012800/1510099200

X = 38

Sale 5:

Bulk for Insomnia Crone’s

Seller: https://backpack.tf/profiles/76561198108035080#!/compare/1510358400/1510444800

Buyer: https://backpack.tf/profiles/76561198095094016#!/compare/1510272000/1510444800

Scorching Big Country Mini:

Sold for Roboactive Professor’s Peculiarity (60) + 10 keys

No outpost

Seller: https://backpack.tf/profiles/76561198053767371#!/compare/1510444800/1510531200

Buyer: https://backpack.tf/profiles/76561198143105719#!/compare/1510444800/1510531200

X = 70

Sellers:

SCM:

http://steamcommunity.com/market/listings/440/Unusual%20Taunt%3A%20Rancho%20Relaxo?filter=tiger

$90.01 (~38)

$99.97 (~43)

$100 (~43)

65 keys:

http://www.tf2outpost.com/trade/29417388 - 3 weeks

75 keys:

https://i.imgur.com/jYnrqNy.png - young, owned for about a week

https://i.imgur.com/pjvIxXM.png - 4 days

https://i.imgur.com/Fyn1prM.png - 3 days

80 keys:

https://i.imgur.com/FdACQCu.jpg - young

85 keys:

https://i.imgur.com/kCaLpXa.png - 2 days

90 keys:

https://i.imgur.com/Pid97Z0.png - 13 days

https://i.imgur.com/qDq7p1d.png - 3 months

https://i.imgur.com/Q0K4HaJ.png - 7 days

Offers:

http://www.tf2outpost.com/trade/29439534 - 1 weeks

http://www.tf2outpost.com/trade/29423505 - 3 weeks

http://www.tf2outpost.com/trade/29448262 - 6 days

Sales at:

38

45

50

62

62 looks like a bit of an outlier here. Excluding 62.

Sellers at ~38 on the SCM support 38 in the range.

Going with 38-50.