Accepted 76561198026133530 (SLOI Selling my hole bp trade me)

Victim:
steamID: Dariusdd
steamID32: STEAM_0:1:41838143
steamID64: http://steamcommunity.com/profiles/76561198043942015
customURL: http://steamcommunity.com/id/DDariusd
steamrepURL: http://steamrep.com/profiles/76561198043942015

Scammer:
steamID: SLOI Selling my hole bp trade me
steamID32: STEAM_0:0:32933901
steamID64: http://steamcommunity.com/profiles/76561198026133530
customURL:
steamrepURL: http://steamrep.com/profiles/76561198026133530

Screenshots (uploaded on puush):
http://puu.sh/152v1
http://puu.sh/152vb
http://puu.sh/152vw
http://puu.sh/152JS
http://puu.sh/152K4
http://puu.sh/152Im
http://puu.sh/152p9

Chat log: http://www.tf2pricecheck.net/Thread-Just-got-scammed

Middleman's profile: http://steamcommunity.com/id/cinic/

IDK what else to say, it was pretty much a misunderstanding between me and the middleman and it all ended bad. I will miss my Ghosts Hallmark.

Middleman here.

It was a big misunderstanding, but it was indubitably a scam. I was playing a game of MvM, and was in the group chat. I asked him to tell me when the payment passed. He said - not in reference to the payment - "Got that." "Okay now."
I read that, and right as I read that, the scammer in question traded me. I gave him the item, and then he posted that he had to leave in the group chat.

I've uploaded the screenshots on imgur:
http://imgur.com/5PJiO,wGfMf,ZzDxg,BLimN,VcmbA,zGTb3,kX5tY#0

Why would you trade someone a hat without double verifying that the payment was complete? There was no indication or conformation that the payment was made. I've done 100's of MM transactions and you can't transact one like this. You need to be in firm control of the whole situation and make sure that both parties are well aware of exactly whats going on. If your going to MM peoples high dollar items you need to understand what both traders are doing and EXACTLY how paypal and other cash transactions work. Request to the user that's sending the payment to post the persons name and amount sent in the chat. Request to the user that has received the payment to do the same and the amount received as double verification. If there is an issue ask for screenshots of the paypal screen. This is just a friendly statement to help you out in the future.

@Bluedemon
What will happen to the middleman though? Is it up to SteamRep or Skial?