Can I add business expenses to my home based business without purchasing the self-employed software? I don't see any other option.

[Carl]

No, not with the online version. If you claim even one penny of business expense, you have no choice with the online version but to upgrade to the more costly Self-Employed flavor.
But with the CD version that you physically install on  your computer you can file the full SCH C and claim expenses on the Deluxe, Premier, and Home & Business flavors.

[SweetieJean]

You are required to claim all of your expenses.

[Ashby · Accepted solution]

No, you do have to upgrade to the self-employed version. The lower versions will allow for income from self-employment, but not expenses.