Re: This does not happen just to sysadmin
As the previous commentard said, outrageous billing is the easiest way to get rid of these (or at least get paid hilariously for your trouble).
When I was at school, one of my friend's dads was a professor in a very specialist area. He was paid vast sums of money to do consultancy work.
One particular job he was offered involved an extended stay outside the country, and he did not want to do it. It clashed with family events and other commitments. Rather than telling them no, he quoted the job at an extortionate rate, 10x+ his normal (already very high) rates. To his astonishment, they accepted. The insane amount of money he was paid was adequate compensation for the inconvenience.