Competition for apartments is fierce in some markets, and tenants with blemished credit can have a tough time getting their applications approved. Although there's no overnight fix for credit problems, there are things you can do to win over potential landlords.

1. Spruce up your credit report. First, order a free credit report, and write to the credit reporting bureaus if you spot incorrect or outdated information. Paying up collection accounts and reducing your debt both give your credit score a boost, and if that means taking on a second job or a roommate, so be it. Even if you need to apply for apartments before your credit score reflects the payments, you'll still benefit by reducing your monthly debt payments, thereby making more money available for rent. 

2. Contact real-estate brokerages and private owners. Apartment complexes often have hard-and-fast rules about who qualifies to rent and who doesn't. Private owners, whether they rent their properties themselves or hire real estate brokers to find tenants on their behalf, may prove more flexible. You can stop in a real-estate office to inquire about their listings, or browse newspaper and online classifieds to find rent-by-owner properties.

3. Apply for properties you can afford. The benchmark for affordability is the percentage of your income available to housing payments. The ideal is no more than 30 percent of your net income. That may be unrealistic in markets with inflated prices, but the closer you come, the better off you are.

4. Treat showing appointments like job interviews. First impressions count. Dress neatly for your appointments, and arrive on time, with all of the decision-makers. In addition, come prepared to show ID and submit all the documentation and information needed for the rental application.

5. Boost your application. You can make up for derogatory information by decreasing the likelihood that you'll default on the rent. A co-signer with strong credit can be helpful, as can paying extra rent upfront. Whereas many landlords require first and last months' rent, an extra month or two of advance payments gives the landlord a cushion in the event they need to find a new tenant before your lease ends. Alternatively, offer to take on some maintenance duties, such as mowing grass in common areas, or cleaning gutters.

If you've done everything you can do to impress a prospective landlord but don't feel confident that you've won them over, write a personal note to add context to the information in your application. Use it to explain a circumstance beyond your control that caused you to fall behind in debt or rent payments, for example, or to explain the steps you've taken to improve your financial stability moving forward. The landlord may appreciate the effort enough to take a leap of faith.