Here is a list of the information many mortgage lenders will use to consider your loan application:

For all loans

Social Security Number, for borrower and co-borrower if any.

Employment History
For the last two years, employment dates, addresses, salary.
Current pay stubs or W-2 forms.

Check and Savings Accounts and Certificates of Deposit
Location of bank accounts, account numbers and balances.
Address of bank if out of town.
Last 3 months' statements.

Stocks, Bonds, and Investment Accounts
Broker's name and address, description of stocks, bonds, etc.
Last 3 months' statements or copies of stock certificates.

Life Insurance Policies
Insurance company, policy number, face amount, cash value, if any.

Retirement Plan
Approximate vested interest value.
Copy of latest statement.

Make and model of automobiles, their resale value.

Other Assets
Market value of personal and household property.

Liabilities and Other Non-Mortgage Debt
Creditors names, addresses, account numbers.
Monthly payments and balances.

Any other income information.

If you're self-employed

Two years tax returns, profit and loss statements, both company and personal if separate.

Current balance sheet and profit and loss statement if more than two months into the new fiscal year, signed by CPA.

If you have income from:
Rental Property
Notes Receivable
Two years' personal federal tax returns.

If employed in family business

Personal federal income tax returns and all schedules for the past two years.

If divorced or separated

Complete executed divorce decree and settlement agreement.

Payment history of alimony/child support over the past 12 months, if it is a financial obligation.

If you choose to have this be considered as part of your income (you don't have to), be prepared to provide 12 months cancelled checks or bank statements reflecting income deposits.

If you own real estate

Name and address of all mortgage lenders for the past 24 months, account numbers, monthly payments and balances.

If you've sold your home but not closed:
A copy of the sales contract.

If you've sold your home, closed, and you will use the proceeds for your new down payment:
A copy of the HUD-1 Uniform Settlement Statement.

If you rent

Name, address and phone number of landlords for the past 24 months.

If you're buying a home

Purchase sales contract or offer to purchase and all addenda.
Furnish contract with original signatures of buyer and seller.

If a source of your down payment is a gift:
Name, address and relationship of donor.
Gift funds will be verified in both the donor and recipient's accounts.
Note: Not all loan programs allow gifts to be part of your down payment.

For FHA Financing:
Evidence of Social Security Number and photo identification.

For VA Financing:
DD214 and Certificate of Eligibility.

For Construction/Perm Loan:
Signed construction with cost breakdown, builder plan and specifications.