My dad has agreed to cosign a lease with me but I am afraid my application will just be thrown out since I cannot provide a credit score or any proof of income. A cosigner for an apartment takes on the financial responsibility for a lease.Learn how having a cosigner can help someone get approved for an apartment. Should you allow a cosigner on a lease? This article covers when landlords should consider a cosigner and what the risks are. This guide will provide all the necessary information you need to screen, process, and add a cosigner to a lease. Adding a cosigner to your standard lease agreement isn't difficult. Rather than writing a new lease entirely, you can simply add an addendum. Having a cosigner for a lease can help you rent the apartment of your dreams but also divides your rights and responsibilities as a renter. Should you and the cosigner qualify, you'll both sign the lease.