Third year doing sole proprietorship, no income. Can I still deduct business expenses?

It depends. The business rules are quite clear from the IRS. You must be engaged in the activity to produce a profit.  One of the deciding factors is the following: 

• An activity is presumed for profit if it makes a profit in at least three of the last five tax years, including the current year (or at least two of the last seven years for activities that consist primarily of breeding, showing, training or racing horses).
  • IRS Fact Sheet
• This is not 'all encompassing' since it does take some time to get a business off the ground.

You can decide if it is hobby or business income.  This IRS link will help you: Business or Hobby?

Key elements:

1. A hobby requires you to report the income you received and under the current tax law, Tax Cuts and Jobs Act (TCJA), no expenses are allowed to be used to reduce the money collected even if you itemize deductions.
2. A business allows you to deduct the costs necessary to obtain the income.  The law explains that 'you must be engaged in the activity to produce a profit'.  The test under IRS tax law is that you must show a profit three out of every five consecutive years to be considered a business.

Once you decide what type of income this is you can use the links below to see how to report.

• How do I report income from self-employment?
• See how to report hobby income below.

Other Miscellaneous Income:

1. Go to the Wages and Income  section of TurboTax
2. Scroll to  Less Common Income > Select  Miscellaneous Income, 1099-A, 1099-C
3. Select Hobby Income and Expense > Enter the income