If you apply for an apartment will your credit be a factor?

To have your credit rating affected by any creditor, they must report monthly to the credit agency. Landlords seldom, if ever, report regularly. They might check your credit before you move in, but usually, the only time you are affected by a rental agreement, is if you default on the rent, AND you get sued for it, AND the landlord gets a judgment against you AND he registers the judgment with the credit reporting bureau. Then, you have an ugly black mark on your credit score.

In order to bypass the legal process and go directly to screwing up your credit, the landlord must be a member of a credit reporting agency, and must report to them about you and all his other tenants monthly. Then, if you are in default, it would show the month following the default, or the second month following. Usually, you get one month grace. But if you are 2 months in arrears, and the landlord is sophisticated enough to be reporting monthly, you would have been kicked out already!