One thing I might suggest is that the payment is made in advance and kept in an escrow. Allowing people to hire a drone operator and then trusting them to pay after the footage is delivered seems like a lot of risk for the operator. It's not normally expected with photography that you get the full deliverables before paying. The pre-pay business model is pretty standard for hire-a-freelancer services too, so I don't think it would detract from the service.