If you are new to Windows installation development, you may not know what the Windows Logo Guidelines specify for applications that are installed only for the current user of a computer.
Here are the exact words on this subject from the Windows 7 Client Software Logo document:
All application data exclusive to a specific user and not to be shared with other users of the computer must be stored in Users\UserName\AppData.
What this means is that, when you are setting the value for INSTALLDIR in Basic MSI or InstallScript MSI projects, you should use the AppDataFolder.
Finally, if your application and data will only be installed for the current user of a computer, you are creating a Per-User installation.