When explaining sales tax during an auction, what key detail must be included?

The inclusion of exemption criteria for items and purchasers is crucial when explaining sales tax during an auction because it informs bidders about any potential tax liabilities they might face. Understanding exemptions allows participants to determine whether they are required to pay sales tax on specific items based on their status or the nature of the items being sold. For instance, some items may be exempt from sales tax due to their classification, or certain purchasers may qualify for exemptions because of their tax-exempt status, such as non-profit organizations or government entities. By clarifying these details, auctioneers help ensure compliance with tax laws and prevent misunderstandings during the transaction process.

The other options, while relevant to the auction process, do not directly address the specific implications of sales tax that bidders must be aware of. Bidding increments, item viewing locations, and auction timelines are important logistical details but do not provide the essential tax-related information that could impact the financial responsibilities of the bidders.