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Total your monthly expenses and debt. Check your credit score. Gather documents to verify your income and debt obligations. Contact at least 3 mortgage lenders.

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If you don't already have a household budget, creating one helps you determine how much of a house you can afford. Since getting a mortgage means taking on significant debt, make sure the debt you already have is manageable.  Once you've totaled your expenses, calculate how much of a monthly payment you can afford. Generally, your mortgage payment should be less than a third of your monthly income. Ideally, it should be around a quarter of your monthly income. While your monthly payment will depend on your interest rate and mortgage term, having a monthly payment in mind helps narrow the range of homes you can buy. Pull your credit report from all 3 major credit bureaus: Experian, Equifax, and TransUnion. You are entitled to one free credit report each year by federal law. For the other two, you'll have to pay a nominal fee.  Use free services, such as Credit Karma or Credit Sesame, to monitor your credit. If you see any errors on your credit reports, notify the credit bureaus and get those errors corrected before you start applying for mortgages. Your credit score will likely go down considerably in the first year after you buy your home. If your score is in the mid-600s or higher, this shouldn't cause you significant problems. When you apply for a mortgage, you'll need at least 3 years of tax returns and 6 months of bank statements. You may also need statements from any investment accounts you have.  Depending on the lender, you may also need insurance statements or other information. The lender will provide a list of documents you need. Gather documents in anticipation to save some time and get a more accurate offer. If you don't have tax returns available, contact the IRS to get copies. When looking for a mortgage, compare several offers to make sure you get the best deal. Apply with different types of lenders – large national lenders as well as smaller, regional banks or credit unions.  If you've had accounts with a bank for at least 5 years, apply with that bank first. Since you already work with them, verification will be easier. You may also get a better rate from a bank you have a relationship with. Because shopping around for a mortgage is the responsible thing to do, multiple inquiries typically won't have a negative effect on your credit score.