Characterization of Gatsby

"One time he killed a man who had found out that he was nephew to Von Hindenburg and second cousin to the devil."

I thought it was really funny all of the random stories and ideas people had of Jay Gatsby. Even more amusing was the fact that all of these people claim that he is some strange killer or evil person and yet they are at his house for a party- most of them uninvited.
I think that it is very difficult to learn about Gatsby because most of the information given to the reader is passed on through other characters in the story. In addition, the information Gatsby gives is questionable (at least to the narrator and Jordan Baker). It is interesting that Gatsby knows people have strange perceptions of him and yet he continues to make himself unknown to the guests at his parties. He mentions to Nick "I don't want you to get a wrong idea of me from all these stories you hear." (pg 65). I think this makes Gatsby seem somewhat suspicious because he is concerned about what Nick thinks of him but no one else (except for Daisy- although it seems as if he cares more about what she thinks of his home and material possessions than anything.) Nick feels that Gatsby makes up a great deal about his past because it seems as if none of his stories match up. Right now Gatsby seems sort of like a flat character because a lot of things revealed about Gatsby thus far cannot be determined to be true.