When buying the assets of a business, some are subject to sales or use tax, while others are not. Items subject to retail sales tax.Business assets are not considered legally transferred without a properly executed Business Purchase Agreement between the seller and purchaser. A business sale agreement is a legal document that describes and records the price and other details when a business owner sells the business. Download Washington Asset Purchase Agreement template, modify and send for signing using BoloForms Signature. When you sell your business, you may need to report all or part of the sale on your excise tax return. Also, you may be required to collect retail sales tax. The process is comprised of four general steps: conversation, letter of intent, definitive documentation and closing. In an asset sale, the new owner purchases the business's physical assets. The seller retains all rights to the legal entity.