9.95% On-Site Items. Sales Tax Rates for Off-Site Items: 9.95% Mansfield, LA; 10.45% Abbeville, LA. Sales tax will be added to the purchase price including buyer's premium of all taxable purchases unless the buyer files with Guinn Auction Company, Inc. proof of exemption from all such taxes in a form that is satisfactory to Guinn Auction Company, Inc. and the appropriate governing authority. Proper proof of sales tax exemption must be provided upon registration prior to placing a bid. If sales tax is not collected and at a later date is determined due, buyer agrees that buyer will bear the liability of the sales tax for his/her purchase. All titled vehicles will be taxed at the DMV upon registration of title.