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 8594 is a tax document required in certain business sales where the buyer acquires assets rather than stock or equity.â–· Attach to your income tax return. 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 goodwill or going concern value. Access forms available from the Assessor's office, including benefits, business personal property, change in ownership, and other general forms. Complete IRS Form 2848, Power of Attorney and Declaration of Representative to represent the fiduciary before the IRS. The most useful item to aid in completing the Form 571-L is an accurate and up to date asset listing. We will require that you provide documentation of all of your income and assets. Contra Costa, CA Treasurer's Office is offering 39 parcels for auction online.