Additionally, the rules of professional ethics prohibit attorneys from working on contingency in family law or criminal law cases, because this would appear to condone or even encourage divorce or criminal activity.
Apply the rule of thirds – 1/3 is your salary, 1/3 is expenses, 1/3 is unproductive time. In this case simple triple the salary you expect and divide it by the number of working days in the year to obtain a daily rate.
To calculate your hourly consulting rate from your working week salary follow these steps: Determine what salary you'd like to make. Take that number and divide it by 52 (number of working weeks), then again by 40 (number of hours each week). Take that number and mark it up by 25% to 50%.