Under the TT Online Self Employed interview, we do not report business expenses under "self employed" income as our income comes from our multiple member LLC. Instead, we report it under "SK-1" income. So, we don't file a Schedule C for our business. We file a Schedule SK-1, along with a Schedule E and form 4562. The Interview screens for SK-1 income/expenses doesn't give me an option to take the 179 deduction on the vehicle I entered.
