Always try Up-selling or Cross-selling

Up-selling is a sales technique whereby a saleperson induces the customer to purchase more expensive items, upgrades, or other add-ons in an attempt to make a more profitable sale. Upselling usually involves marketing more profitable services or products, but upselling can also be simply exposing the customer to other options he or she may not have considered previously. Upselling implies selling something that is more profitable or otherwise preferable for the seller instead of the original sale. A different technique is cross-selling in which a seller tries to sell something else."