Buy recruiters at your current company a beer. If you keep in contact, especially once they've left, you can get all sorts of information.

It is good advice to treat recruiters with respect. All too often on HN I see an attitude of contempt shown towards recruiters (and HR in general).

That contempt is earned from a history of doing things that make articles like this one necessary.

I agree, but there is nothing to be gained personally from doing so. It is like being rude or contemptuous to your waiter.

Why would they charge? They get a placement fee based on a percentage of the starting salary. It's in their interest that the candidate gets the best deal possible.

They get their fee if you are placed. This puts them in a conflict of interest situation where if they can convince you that you are worth less than your true price you will be easier to place. Also the cheaper you are the less work they will have to do to get you placed in a new position.

You really only want advice from someone you are paying and who cannot benefit from under pricing you.