There are 3 main areas for qualifying the applicants for your rental property.
First, as a landlord, you should be familiar & practice Fair Housing Laws. You can not discriminate against protected classes. You should also deliver to the applicant the Qualification Criteria form before they apply.
Second, You must run a back ground check including criminal, rental, eviction, and credit. Using the right tools are essential in this process & you must rely on a very comprehensive system that covers a nationwide data base.
Third. A through examination of income& employment will determine the persons ability to make the monthly payment. Make sure the employment is contiguous & not a temporary job and the W-2s & pay stubs are verified as well.