Commission Painting; Your Thoughts

Old School here with a question for the blogosphere. What are your thoughts, opinions and experiences on commisiion painting and conversions.
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As time goes on, the members of Dark Future Games have picked up more and more conversion work around the FLGS and to a lesser extend other areas and all the the folks we do jobs for seem pretty happy. We don't charge the prices that you see on the internet, so we were wondering what folks out here thought of commission painting in general. Have you had good or bad experiences? Has price prohibited you in the past? What kind of work would you (have you) have done and what would you just paint yourself? Do you prefer when comission sites offer prices up front? We are looking for any and all feedback as all of the combined experience out here is greater than what anyone could ever muster alone, so please post away.