First suggestion, be kind :)

Sale 1:

Quicksold for 49:

Sold on Outpost for the B/O within a day:

https://imgur.com/a/PqWYqez Sold for 49 keys

Owner's Outpost listing: http://www.tf2outpost.com/trade/29758918 (created August 30th)

Gonna exclude because it sold in 1 day as a quicksell.

Sale 2:

Sold for 80 pure:

My B/O was 80 pure: http://www.tf2outpost.com/trade/29760779#latest

Sale: https://backpack.tf/profiles/76561198209640976#!/compare/1536192000/1536278400

Seller at 90: https://backpack.tf/stats/Unusual/Razor%20Cut/Tradable/Craftable/9

Only valid sale at 80

Gonna go with 80 flat.

Any constructive criticism would be appriciated in the comments :)