Depends on your contract with them,

For example, for my commercial clients I charge 50% upfront to cover studio hire costs, any equipment hire, models, etc for a shoot. The rest is paid on the delivery of the images.

I have seen in the past where tradies have an upfront materials fee but it's always agreed before hand, either verbally or normally in a written quote.

Posted By: I Am Hoot, Mar 7, 11:53:15