Based on an interview with Srdjian Gavrilovek, an investment banker in Atlanta, GA.

Lenders only make their money when they loan money. Therefore, they want to loan as much money as possible. But, there are qualifying criteria that borrowers must meet. Some loans will require high credit scores and lots of income, while other loans will permit a lower credit score, and less income. For the average buyer, government insured loans such as FHA or VA may be easier to get. But in general, your mortgage lender will ask you to meet certain underwriting requirements for your loan.

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