Contact your chosen lender as soon as you have ratified (under contract). You’ll coordinate with them on finalizing the loan with the property’s specifics and final sales price. You can expect the lender to request more financial documents from you.
It’s very important that you don't do the following from this point until after you close:
Don’t change jobs, become self-employed, or quit your job.
Don’t make any large purchases, even if you aren’t financing the purchase.
Don’t fall behind on any payments.
Don’t spend money set aside for closing.
Check with your loan officer before making any large deposits - you may be required to provide additional documentation about the origin and nature of the deposit.