Checking reputation for trading

I just look over here. If someone has a high positive trade feedback, and minimal negative trade feedback, that's fine by me.
There's always a risk, but it's possible to minimize it.

If someone's acting shady, it's time to get nervous. If youre doing a big trade, agree to do it in installments. If someone has no feedback, make them go first (not so easy if you both have low feedback).

So i was wondering, how the site Steamrep actually workes..

If an user was reported as a scammer on their forums, you'll see a "Warning: User Reported for Fraud" message. It also tracks users which were trade banned by Valve, but you can check that on their Steam profile.

if i find more than 2 negative rep in Steamgifts , i ignore the trade
today someone wants to give me csgo key for Call of Juarez: Gunslinger code , he asked me to go first :) xD

Use Enhanced Steam add-on on Chrome browser and check the trader Steamgifts account before trading with him.

Rep, no matter what site it's on, is completely useless as it can be faked (and it is very often).
I see a lot of "+rep my profile and I'll +rep yours!" posts on the announcements for bundle site groups, just as an example.

As NerdHouse mentioned, it's useless. Especially the +rep comments on profiles. About a year ago when I used to trade my bundle keys, I looked up the persons steamtrades reputation. But I've been scammed by a person who had high reputation there, so I think all these reputation sites can be faked, so be careful and listen to your instincts. Cancel the trade if a person seems fishy even a little bit, espacially if you trade more valuable stuff.

i use rep on steamgifts, bcs you can delete posts on your profile on steam.....about steamrep site, i dont know how it really works, but i did already a lot of trades and still cant see any good reputation, maybe it is used only to report scammers
so far i have 959 trades on steam and never got scammed, maybe it is bcs i dont trade big value stuff (very rarely)

Barter.vg uses SteamGifts too for reputation checks. The one here is more trustworthy than profile ones, but as it was said, it can be faked to a degree. Add on some SteamReps to see if there are reports, and that's about it. Generally it is lower rep going first, but ig you were contacted by the other party, you can try saying that since they contacted you, they go first.
Also, for the first few dozen trades, try to stay in cheap bundle territory. Saying you want to trade for GTAV with 0-5 rep tends to be suspicious.