The GoldFinch Sales Tax module can be used to calculate Use Tax on purchase orders.
Read Sales Tax V1 on how to set up Tax Area, Tax Jurisdiction and Tax Details.
Calculating Use Tax on a Purchase Order
Tax Area and Tax Liable for the Buy-from Vendor Account is copied to the Purchase Order.
Tax Group for the Items on the Sales Line is copied to the Purchase Line.
GoldFinch will calculate Use Tax upon saving the purchase order based on Tax Area, Tax Group, and Tax Liable flag.