How would you know if the person they are trading for is a scammer?

I am pretty sure the rules said that you can't make a trade on behalf of someone else.. It doesn't say that anymore, so can I make a trade for another player now?
example: http://www.tf2outpost.com/trade/4920400

The Once, you are incorrect.

If your trade contains items A, B, C, and D, if someone searches for ANY combination that includes at least one of those, it will come up in the results.

Someone does not have to search A + B + C + D to find your trade, just A or B or C or D

Even though I don't have enough cash to donate.. Perhaps lvl 4 donors should exist.. But don't let just ANYONE have access to that status. Let it be people who have been on the site for 3-4 months, or have only a week for people to donate to get in. Exclusiveness? Maybe no on the last part.

Not if they are advertising something I am not searching for, no it does not.

No, it won't change unless you make it a new trade

When I last used the warehouse, all the bots were in a group.. Can't seem to find the group right now ( found it via a bot page)... Not sure if it is the same case, but I think that should be reported to steamrep or something. Unless of course their inventory had a few thousand, unsorted items.

I think it is more of spam. They are advertising their trade in their other trades.

Example: I search for people selling keys. Someone who is selling keys puts ALSO SELLING STUPID THING YOU HAVE NO INTEREST IN!@!!

Alright.. Maybe that jerk will get banned finally ^.^

Also, what about linking to your other trades in a trade?

Oh, I must also ask this.
What about having a massive 2-3 page (scroll wise), identical description advertising EVERYTHING you are selling?