When the other party was anonymous 

     Not real estate, but this happened to me about 20 years ago on a business trip:  One morning somebody was beating on my motel room door.  When I opened the door, a deputy sheriff was standing there.  My rental car parked in front of the room had a dent in the driver side door, and the window was smashed (Mercury Marquis).  The cop asked if it was my car.

    A scantily-clad woman standing behind the car was screaming about something.  Some other girls were standing across the way watching this scene unfold. A lady cop took the hooker by the arm and put her in the back of a police car.  

    Yes, red flags were flying and it was a shady situation. 

Whenever someone is not "straight" with me, it's a red flag and my gut tells me to watch out or get out.

When buyers will not call you back, RED FLAG.

Not me.

Yes. I once had a guy offer to purchase my cow for "magic" beans. Something about him made me think this was just a scam. A few days later the paper reported he sold the beans to a widow's son, Jack, and they ended up making a mint. Looks like I'm the one with egg on my face!

Meet Slim Shady...

Was never in such a situation. What kind of red flags and shady situations are you referring to?

What other agents have said, not telling you the whole story, or telling you one thing then saying something else the next time you speak to them. Those are red flags that mean something could be a little shady.

If stories do not match watch out....

Trust your judgement.

It think Fred Griffin has a good answer.

When people do not communicate or provide the information requested. Sometimes it's just a gut sense something is not right

We both have that 6th sense, and usually act on it promptly.  Things don't add up in the initial conversation.  A

Nothing was in writing...

No,

No

When beign questioned by Anonymous.

Experience along with your gut instinct should be your guide.  In shady and non-shady times alike.  

Yes, many times.

You always need to be alert.

As soon as I realize it can be a shady situation, I focus on fixing it or eliminating it entirely. 

When the color was turning red....lol!

Rarely we get such notices! They come as a surprise!

Of course, most are easy to spot.

Go with your gut - it serves you well!

Well yes and this is a very GENERAL question to post anonymously lol

No lender letter.

common sense always guided me.... plus the Golden Rule.... 

just do the right thing

Yep.  When my "spidey sense" started tingling.

Diana Dahlberg has an answer I agree with.

Evasiveness, double-talk or not returning contact is not good

I hold out for the checkered flag

Yes, you can usually see or hear or feel red flags by simply talking to people before you start with them. When it sounds too good to be true, it usually is

When the grand prince of King Maliamark wanted to buy the house listed, sight unseen and would OVERPAY so I could extract a generous professional fee from the overpayment.

That may contain more than one red flag.

Yes, never believer everyone is honest!