Some great pointers; however...
From the CPA world, one of the top five deductions that increase the risk 10-fold that your return will be flagged for review and possible audit is claiming home ofice deductions.
Legit expenses or not, the rules around claiming home office deductions are quite narrow. There are few people if any that can legitimately qualify for it.
Act Happy, Feel Happy, Be Happy with no reason in the World (D. Millman)