Up Selling is a marketing term for the sales strategy of suggesting related higher priced products or services to a customer who is already considering a purchase. The attempt is to gain more profit by getting the customer to buy for example:

• a more expensive item of the same type of product
• an add-on to the product in question

A common additional sales technique is Cross Selling.

• http://www.buzzle.com/articles/upselling-vs-cross-selling.html