Maintenance is covered automatically for as long as you subscribe to Centrex. Feature offerings are sometimes limited and governed by state regulators. Management of system may be delayed due to batch processing. Depth of system management may be restricted. Features are incremental costs for packages or individual features.
Costs are monthly recurring for the life of the system.
Telephone options are numerous and standards based, from basic to digital. Existing analog instruments can be retained. Maintenance is covered 24 hours a day with no extra charge for system life. System upgrades and expansion is automatic with no extra charge. Phone companies are fully prepared for disasters and switch failures with standby emergency equipment.