After careful consideration of your rental application, I regret to inform you that we have decided not to proceed with your application at this time. Your letter should have a professional and informative tone, covering exactly why you're denying their rental application.A rental application denial letter, also known as an adverse action letter, is a formal document that a landlord or property manager sends to applicants. The form you need to respond to an eviction case is Answer - Unlawful Detainer-Eviction (form UD-105). You should always act fairly, professionally, and compliantly when rejecting rental applications. Check out our guide below for the best practices. In this article, we'll talk you through what's included in a rental application denial letter and even give you a free template to use.