Credit to Aaron and fireman (why no resuggest ;-;)

99 keys

Sold for Harvest Counterfeit Billycock (open at 65) + Duped Harvest Buckaroo's (40)

Seller before: https://backpack.tf/profiles/76561198020676615?time=1433729592

Seller after: https://backpack.tf/profiles/76561198020676615?time=1433833200

http://backpack.tf/profiles/76561198020676615?time=1433660400&compare=1433833200

Buckaroo's mini: 40 keys

Sold for 40 keys

Buyer before: https://backpack.tf/profiles/76561198006544512?time=1430377200

Buyer after: https://backpack.tf/profiles/76561198006544512?time=1430463600

http://backpack.tf/profiles/76561198006544512?time=1430377200&compare=1430463600

(was a sale for 110 that was an outlier)

http://www.tf2outpost.com/trade/26162932 b/o 98 keys Sold for Misty Skull Swagman's Swatter + Vivid Plasma Your Worst Nightmare

http://www.tf2outpost.com/trade/26640582 Sold for Morning Glory Tartan Spartan (102.5 keys outdated) Current seller 90 keys http://www.tf2outpost.com/trade/26630922

http://www.tf2outpost.com/trade/26510441 Sold for 64 keys pure + 1 bud + ~ 27 keys in items.. Making this ~ 95 keys.(Was willing to take 85 keys in the comments)

http://www.tf2outpost.com/trade/26630328 b/o 90 keys. Sold for Circling Heart Fruit Shoot(46 keys) + Phosphorous Connoisseur's Cap(47 keys outdated)

Current seller

http://www.tf2outpost.com/trade/26766249 (has had multiple trades up for 88 keys for around a week

So we have 4 sales and 1 seller less than your suggested range here. Seems that sales are commonly revolving around the 80-100 keys region. I would probably go with 80-100 keys. 110 keys sale is probably an outlier with all these sales. Either way, all these sales and seller should not be ignored.

Seller at 88 and sales at around 90 - 100 rounding up 88 - 100 to 90 - 100.