Entity choice and tax election — sole prop vs LLC vs S-corp election timing depends on projected net income; the wrong election costs thousands. Payroll tax — Federal 941, FUTA, state SUI, W-2s, 1099s. Missed deadlines compound; the IRS Trust Fund Recovery Penalty for unpaid withholding is personal. Sales tax across jurisdictions — even with software, registration, filing cadence, and audit support benefit from CPA review. Depreciation — Section 179 and bonus depreciation on a truck and equipment can shift large deductions into year one; the IRS code on this is dense. Year-end planning — Q4 conversations about estimated tax true-up, retirement contributions, and equipment purchases convert tax dollars into savings. Audit defense — a CPA who prepared your return can respond to IRS or state notices. Annual fees commonly $1,500-$4,000 for a small operation, more for monthly bookkeeping. A licensed CPA or attorney in your state should review your specific situation.