You (or the purchaser or transferee) must complete Form CBS-1, Notice of Sale, Purchase, or Transfer of Business Assets. Each sale has different pros and cons.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. To sell a business in Illinois, you'll need various legal documents, including a bill of sale, asset purchase agreement, and non-disclosure agreements. Free Consultation - Call (312) 889-8702 - The Castle Law Firm helps companies with business matters in Business and Franchise Law cases. 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. Form 4797 is used for reporting the sale of various types of business property, such as real estate, equipment, and assets used in a trade or business.