Categorizing taxes on my salary vs. self-employed income
I made a small amount of money renting my car out via Turo this year as a business, at a net profit of $589. I'm trying to figure out how much of my overall taxes being paid are attributed to the Turo business versus my salary/overall income. My total income for the year falls into the 24% tax bracket so my thought would be that as the $589 is incremental, I'd be paying 24% (incremental federal) + 15.3% * .9235 (effective FICA taxes for self employed) + 8.25% (incremental state) = 46.38%. This doesn't seem right though especially when I play around with the turbotax calculator. Can someone help me with this since I would like to know what my real net earnings after tax are on the business.
One more question regarding this income: I paid a general excise tax on the gross receipts for this activity to the state. Is this tax deductible and if so, where can I enter the deduction?