Alright, so I've been PM'd by a few people what red-flags to look out for since I have a pretty good track record of spotting scammers. Sometimes I get it wrong, but better safe than sorry.  Here's a couple rules to follow to avoid becoming a victim:

1. Newbies, NEVER DO BUSINESS WITH OTHER NEWBIES, EVER. There are plenty of veteran members to do business with and ALWAYS use escrow. If you're a newbie and you're doing business with another newbie, there's nearly a 100% chance that one of the parties is a scammer. I can not stress this enough.. just work with people who have been here at least a year.
2. Always use escrow.
3. See rule #2.