As a tax preparer.....I WOULDN"T TOUCH YOUR TAX RETURN either....Hopefully, your MIL is a licensed tax preparer, and is willing to go to a tax audit with you! I just completed an audit for a mechanic, out of his house, grossed $28000, expenses of about 14000....After 2 years of "checking" his return, his garage, receipts, bank records (personal and business)and HIS TIME spent getting records and meetings together...The IRS got him for another $100, they disallowed some expenses!!! They are currently checking into the previous 3 years....REMEMBER a man named Al CAPONE.....#! Mafia guy...but they got him on tax evasion!
EVERYONE is correct in this being a wide open field for the IRS and don't forget your STATE tax division! Not worth the savings!!!