Do you have a standard pricing system for your service? If so, please share the details here.
The best way to determine what, how much you will end up paying, is to decide with specifics; what kind of service you need/want.
What types of customers have you worked with?
Overnight Security Services, Patrol Services, Event Security, Office/retail/private security officers.
What advice would you give a customer looking to hire a provider in your area of work?
Research references, ensure company is a legitimate business that has all necessary licenses and paperwork such as: bond, ppo, insurance etc.