Perhaps you were pre-approved prior to or during your home-hunting activities. Pre-approval can take place in the absence of having identified a home to purchase.
When you enter into a contract to purchase your home, you begin the process of obtaining final loan approval. To convert your pre-approval to final loan approval, the main items the lender needs include the appraisal, purchase contract and title information. Your real estate agent, loan agent and attorney (where applicable) will be instrumental in providing these documents to the lender. 

If you were pre-approved, you probably gave many of these documents (below) to your lender. Review the list to make sure the lender has current documents. If you’re just beginning the approval process and the lender will be verifying your income, assets and liabilities, you’ll need to gather these documents: 
 

A.  All Borrowers:

• Copy of purchase contract
• Copy of sales contract on real estate you are selling
• Divorce or separation documents
• Bankruptcy files
• Relocation agreement
• Copy of most recent Social Security check
• Award letter and copy of most recent checks for disability, retirement, or legal settlement
• Recent statements for all credit card accounts
• Bank and financial brokerage account statements for the previous three months
• IRA, Keogh and 401(k) statements for the previous three months
• Title documents for automobiles under five years old

B.  Employed Borrowers:

• (Documents in section A.)
• Pay stubs for the previous 30 days
• W-2s for the previous two years
• 1099s for the previous two years

C.  Self-Employed Borrowers:

• (Documents in section A.)
• Federal tax returns for the previous two years
• Year-To-Date Profit-and-Loss statement for your business