Every once in awhile, I'll look over real estate and rental ads on Craigslist.org (Atlanta). It took me one time to receive a canned scam e-mail response before I decided to pick up on things. This list is just from my personal experience, and is not always true in 100% of the cases, but for the most part, they are:
1. The ad says "no pets" in the text, but the poster has selected that cats and dogs are okay.
2. You send an e-mail, regardless of its content, and you are responded with, "thanks for your interest. Before we can proceed, please go to this website.......and fill out the credit application so that we can run your credit." You should never....EVER.....provide a company with your social security number over the internet. If a landlord or real estate agency wants to run your credit, they will have you come into the office...after actually seeing the property...and have you fill out a credit check application at that time.
3. The headline reads $900/month, but the text reads something different.
4. If it's too good to be true, it is. If you see a 4BD/3BA house, fenced yard, swimming pool, in a nice area that is being advertised for $600 per month rent...for the entire property, it's a scam (or has a large gaping hole in the roof).
5. If someone tells you that they are a real estate agent ("RE agent," "RE," etc.), sends an e-mail from a yahoo, gmail, etc. e-mail address and want information from you, send an e-mail back requesting credentials (their office's telephone number, name, their RE license number, etc.)