To solve a problem that the price of a personal computer (PC) is unnecessarily high because applications (APs) not required for a user the initially installed when the PC is purchased.

The incentive business system is constituted of a PC maker 40, a user 20 installing APs in the PC to use them, an AP maker 30 for supplying individual APs, and a credit institution and a financial institution 50 for checking and settling credit. The PC maker 40 attaches only the installer of APs to a PC and sells the PC. The user 20 starts the installer, connects the PC to the web site of the AP maker 30 by using the website URL of the AP maker 30, sends the PC type name, manufacturing number of the PC and a credit number to the web site. The credit institution and the financial institution 50 check and settle the validity/invalidity of the credit. When the user 20 downloads target APs, the AP maker 30 totalizes the number of downloaded APs and pays an incentive charge corresponding to the number of contracted download APs to the PC maker 40.