"Casting" covers a wide variety of different activities with different requirements. A little more information on exactly what you are doing would be helpful.

Do you want to charge by the assessment or by the day?

LB

Depends on the amount of work - I usually have my own daily rate and if I do a couple of hours would charge pro rata - up to you what your daily rate is and how much you want the work. I suggest you look at some local H&S companies and see what they charge and perhaps charge a little less to encourage the business. also depends if you intend to travel - how far, will you charge travel time, petrol etc.