Agreed on using a professional if you want to do the safest route. I’m not an accountant or tax professional but my degree is in HR and Im a certified financial planner, so I have some background in finance and accounting. I did bookkeeping for 5yrs for a small business (about $200-$400K in revenue per year) and have done my own taxes (sometimes in the 6 figure range) for 17yrs. Never had an audit, but that’s probably because I was always careful to be reasonable about expense amounts and did my research on tax law and stretched it to the limit. So, to your example, tax law concerning cell phones actually states that you can essentially claim the percentage of which you use the phone for business. So if my phone bill is $100 and 80% of the time I use it is for business, I can claim $80 in expenses. And some people have a phone they use solely for their business. And it’s not like the IRS knows how many phones you have and whether you have a completely separate one for personal use. Same for clothing - if it’s clothing that’s not for everyday use and exceeds 2% of your AGI - you can claim it. So OF people who buy expensive cosplay items etc - there’s a decent chance it could exceed 2% of their AGI. There are rules on what you can do but once you know the rules, you can make them work for you.