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I am trying to get everything all set for us to purchase a house. We have just started looking at houses, but now we need to start looking into mortgages as well. What kind of information do mortgage services companies need in order to process your mortgage application and what do they need to know in order to preapprove you or quote you the rate that you would be able to get from them for your mortgage if you should use their company? Where can I find out more about this? I want to know enough about this so that I don’t make a costly mistake.