Yes!!
We are also a service based business. What I have found is that when you create a service item, leave the item price completely blank. This allows you to assign a custom price each time you add it to an invoice, it never stays or carries over. For instance, we have to apply for city permits for many jobs, but the permit price varies depending on the zip code. So I created a 5 minute service item “Permit” with a $0.00 base price. Each job needed, the technician calls the local building department and adds the price when he adds the item.
hope this helps!
