Think in demand, not labels
A tank is usually compared by storage and recovery. A tankless unit must be sized for flow and temperature rise, especially when several fixtures may run together.
Installation conditions change the project
Fuel piping, venting, condensate, electrical service and location can make a replacement simple or extensive. Ask what changes are included in the estimate.
Maintenance still matters
Tankless equipment is not maintenance-free, and tank equipment benefits from inspection too. Water conditions and manufacturer instructions influence the service plan.