You (or the purchaser or transferee) must complete Form CBS-1, Notice of Sale, Purchase, or Transfer of Business Assets. To sell a business in Illinois, you'll need various legal documents, including a bill of sale, asset purchase agreement, and non-disclosure agreements.If you need additional information, you may call our Chicago office weekdays between a.m. In an asset sale, the new owner purchases the business's physical assets. The seller retains all rights to the legal entity. Use a Business Bill of Sale to set out the terms for the sale of a business and transfer the ownership and all assets to the buyer. This contract sets out the key terms of the transaction, including the purchase price, payment terms, and the assets and liabilities included in the sale. Assets approach: Calculate the total value of all assets and subtract any liabilities to determine the net value. Use Form 4797 to report: The sale or exchange of property. The involuntary conversion of property and capital assets.