The present competitive market situation requires manufacturers to constantly provide superior service and support. As a result, warranty concerns become an important tool for improving product marketability. This research analysis delves into the warranty period for a system, which is divided into two parts: the basic warranty period, which utilizes a fixed free repair renewing warranty, and the extended warranty period, which employs the k-policy. System failures are rectified via imperfect repair through phase type quasi-renewal processes when the system fails during the basic warranty and extended warranty periods, respectively. When the system fails, the failed component is replaced with a new one and a new warranty period is associated with the renewing fixed warranty model. In the extended warranty model, the operating and repair times are modeled to use an alternative phase type quasi-renewal process. Failures occur at any point in time. The system’s condition after the repair has not been as good as before the repair. By using k-policy, an explicit expression for the long-run average cost rate is obtained for the extended warranty model. To illustrate the usefulness of the proposed model, a numerical example and sensitivity analysis are provided.