When completing the form you must: • List all assets you own or control as of January 1, including those assets fully depreciated in your. Taxpayers can complete transactions on MyTax DC or call 202-727-4TAX.Sign up for reminders. The county does not grant extensions for filing a personal property listing after the due date. § 102-38.180 May we sell Federal personal property to a Federal employee? The Washington Department of Revenue (DOR) requires property taxes be applied to real property and business personal property (business assets). Information and sample forms to be used when you need to claim that some of your property is exempt (protected) from being taken to pay a debt. O'Connor was elected Marion County Assessor in 2010. The County Treasurer holds a key position of public trust in the financial affairs of local government. The Washington County Treasurer's office is pleased to offer a range of helpful information for the taxpayers of Washington County.