For tax return preparation in Chula Vista's Third Avenue Village, American Tax Service has operated as a sole-proprietorship practice since its founding in 2006. Individual federal and state returns cover W-2 wage-earner filings, Social Security benefit taxation, and self-employment Schedule SE calculations — the same income documentation that personal-lines carriers including Willy's Insurance Service Inc reference when underwriting life and disability policies for South Bay residents. The firm handles electronic filing through IRS Modernized e-File for faster refund processing and prepares paper returns for taxpayers who require physical submission. Schedule C sole-proprietor filings include Form 4562 asset-depreciation schedules, home-office deductions calculated under both the simplified and regular IRS methods, and vehicle-expense tracking — detailed return work that positions the firm within Chula Vista's Third Avenue accounting cluster alongside CHULA VISTA CPA | TAX CPA. The practice prepares California Form 540 returns with Schedule CA adjustments for state-nonconforming items including Roth IRA conversion differences, health savings account deductions, and state disability insurance exclusions.