A service plan can include a set number of service calls per billing period, but there's nowhere to see how many have been used and how many remain.
Service managers want to track completed service calls against what the customer's plan includes. That way they know when a customer is close to or over their allowance and can bill, upsell or renew accordingly.
Request: show service calls used and remaining for the current period on the customer's service contract, and when creating a new service call for that customer.
Vote and comment if you sell service plans with a fixed number of visits.