Final answer:
Add-on services may include warranty, extended credit, layaway plans, alterations, and delivery & installations offered by sellers to enhance the buying experience and provide value to customers.
Step-by-step explanation:
Add-on services may consist of Warranty & Extended Credit, Layaway Plan, Alterations, and Delivery & Installations. These services are offered by sellers to enhance the buying experience and provide additional value to customers. Warranty is a promise to fix or replace the product within a certain time period, while extended credit allows customers to make purchases on credit and pay later. Layaway plans involve reserving an item by making periodic payments until the full amount is paid, while alterations refer to making changes to a product to suit the customer's preferences. Lastly, delivery and installations services ensure that products are safely delivered and installed in the customer's location.