Nothing to start with, unless you are making a formal application.
Keep in mind that an approval for a mortgage usually has a time frame.
If you don't find a property within that time frame you may need to at least update.
After you meet with a lender and you know your buying ability, then choose a local real estate professional to help you find a great property, and then formally apply for a loan.
You can use the time you are looking at properties to also prepare all the correct and current forms that the lender will need for your formal application.
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