An activity is presumed to be carried on for profit if it produces a profit in at least two of the last five tax years, including the current year.

On Schedule C, you can put your social security number in place of the EIN number.

If you have a net self-employment income of at least $400, you must file a tax return.

If you are self-employed and have more than one business, report the income and expenses of all businesses on one Schedule C.

FIFO stands for "first in first out"

Business income information may be reported to you on: 

What form is used to claim business use of home?