How long does it take for you trust a person?

I can decide it in the first meeting with the person. Meeting doesnt mean first impression. Shaking hands with him/her,looking in his/her eyes when he/she is talking to me and the way he/she talks,the words used while talking.

It is the same with me. It depends on the first impression I think. When I have good feeling from the person it is much easier for me to star trust this person. If I dislike the person for any reason or just have strange feeling about the person it is really hard to gain my trust. Mostly this first impression work for me well.

I don't think you are cynical. I have had tons of experiences where I thought that I just made close friends, then, months later, I would realize that we just are not as compatible as I originally thought, and that they don't have the same values that I have. Generally it takes me about a couple months of talking to a person on a regular and in depth basis. I also noticed that people whom I have known for longer have earned both my trust and respect than others. This is probably because those are the people who I am compatible with enough to stay friends with I guess.