Upgrade with Base Lease Extension
Use
You can use this function to upgrade a leased object if requested by the lessee or to exchange individual components of the leased object; at the same time you can extend the base lease. Because you change the term of the lease, you have to create a new payment schedule.

The lessee wants to extend the lease by six months and either upgrade the basic model with a new component or exchange it for a new model.
You make this change at item level, which means that it applies to individual contract items. You can make this change manually only by choosing Actions; you cannot make this change as an option.
In SAP Customer Relationship Management (SAP CRM) you use the process RESC to execute a product upgrade. The change process UBLX (Upgrade with base lease extension) is created and assigned in the Lease Accounting Engine (LAE, SAP ERP).
Prerequisites
● You have a current lease with the status Released.
● You have created upgrade products in the master data in combination with corresponding item category groups and have assigned these to the relevant products as possible upgrades.

When you execute an upgrade with base lease extension, the application can automatically create the relationship between the product and the upgrade product only if these have been assigned correctly.
If you want to execute an upgrade with base lease extension:
● Execute the process RESC with a base lease extension.
● Enter an upgrade product as a new item. The initial change process is set from the financing product (master data). The system automatically creates the upgrade relationship between the product and the upgrade product in the contract.
● As soon as the system finds a relationship between the product and the upgrade product, it calls EC function modules via an event. You can use the event handler table CRMC_EVENT_CUST for customer entries.
● The function module CRM_CHNGPROC_I_CREATE_OW calls the BAdI to which the required LAE processes are assigned. The upgrade relationship is entered in the field CHNG_PROC_ACC.
● When you incept the contract, the system executes the required LAE process.