You (or the purchaser or transferee) must complete Form CBS-1, Notice of Sale, Purchase, or Transfer of Business Assets. In Illinois, there are two separate but complementary taxes upon the sale and use of tangible personal property.Use Form 4797 to report: The sale or exchange of property. The involuntary conversion of property and capital 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. 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. Use Form 4797 to report sales of rental property, depreciable personal property, land and buildings used in a trade or business, goodwill, etc. This Drake Tax article discusses the sale of an asset used for personal and business use.