What does it mean when your application says preliminary?

A preliminary application is an application for your name to be on the list for the section 8 program. It will ask you for information including your name and address, date of birth, information about any and all family members who plan to live with you, anyone's income and criminal record history. When you're name comes up on the waiting list, more applications will be sent to you, including those that ask for your financial information and authorization for a criminal and/or credit background check.