This has come up, fortunately or unfortunately, a lot in the last few months.  Talking money usually freaks people out, especially if you're setting your own prices.  I've had my good and bad moments dealing with club owners, restaurant owners, wedding planners, etc., but what I've learned is that if you're upfront with people, guidelines are clear, numbers are concrete, deposits paid, and signatures signed, you'll feel much better after a gig and have very little keeping you up at night (like what happened to me recently)...