More often than not: $0. :D I mean they are supposed to pay me in the $200-1600 range, but actually getting clients to fork up money for a completed job is difficult, to the point where I'm ready to give up and get a regular job.
I don't generally do jobs for less than $200 though. It takes times to do research, switch environmental and your head around, but clients sometimes think I'm a typist and should only be paid for time on the keyboard.