In 2019, according to the National Society of Accountants, the average fee for tax preparation was $294 if you itemize your deductions. Please note, that as with any average, your fee may be lower or higher than this. Time and complexity are the main factors when determining the price of tax preparation.
An extreme example would be someone who presents a disorganized box of receipts or is missing documents. Situations like these take more time to sort through, the added time increases the cost.