As the buyer of a business, you could be liable for the unpaid taxes of the business. If you make a casual sale, this sale is subject to retail sales tax.Comprehensive guide on How to sell your business in Washington State. Successfully sell your company in the Pacific Northwest. Both the seller and purchaser of a group of assets that makes up a trade or business must use Form 8594 to report such a sale if:. When you purchase or sell an asset, you must retitle all property in the new owner's name. This includes leases and equipment titles. The process is comprised of four general steps: conversation, letter of intent, definitive documentation and closing. The buyer of business assets and the seller must independently report to the IRS the purchase price allocations that both use. The Washington capital gains tax adopts the federal definition of "capital asset" when determining the taxable gain from a sale or transfer of the asset.