You might want to judge a person by the looks, by the way he acts, by his or her skills.

This will lead you to a perception of them.
Maybe then you’ll have a chance to talk with them and you’ll be more close to them.

But at this point you shouldn’t start underestimate them.

Keep always in mind your perception and maybe reevaluate them, but never take them lightly.
More often than not you’ll end up regretting it, not because they’ll trick you, not because you might be seen as weak, but because you might overlook what’s important.

A work relationship is that: Work.