A "Notice to File Online" will be mailed out in February, which will include the information necessary to file your property statement online. Estate Without Administration (DE-300).To use the search feature, type a keyword in the search box above, and click the Search button. The Tax office is located in the municipal building located at 237 S. Pavilion Avenue. Our mailing address is PO Box 188 Riverside, NJ 08075. The Treasurer and Tax Collector mails the Annual Secured Property Tax Bills each year in October to every owner listed on the Secured Tax Roll. Click on Tax Bills if you want to search your Real Estate, Personal Property, Motor Vehicle or Supplemental Bills. The Tax Collector office collects real estate, personal property, motor vehicle and sewer assessment tax. If the property is personal property (e.g. This will be going out for bid soon. FINANCE.