I try to trust my instincts, because they are usually right. if someone is 'creepy' to me or I get a negative vibe, i try to stay away.
I see how i feel after being around someone- and if they drain my energy, i try to stay away.
I find that a lot of times if there is a quality in someone that I do not like-if I look at myself, I find that I have the same fault. But not always in the same extreme as the other person.
I guess maybe I'm not sure what you mean by 'taking anothers inventory'. But if i have an opinion about someone, especially in the work place, it's better kept to myself I think.
As far as being judgemental, i am sometimes, but I find that the more mistakes I have made in life-the less judgemental I am of others.