Last year I purchased Turbo Tax with Expert, this year I want to down grade the package to Basic. How do I down grade package? The option isn't available.

If you don't want to use Assist & Review this year, then you will have to start a new return. Instead of transferring your return from last year, click on "Create A Different Return".

"Basic" is not available in TurboTax Online, it is only available in CD/Download form (for Windows).