It is impossible to provide a list of every single item you will need to process you loan; the reason is that everyone's situation is different, and until that situation is known by the lender (which does not happen until the application itself begins), it cannot be determined specifically what is needed. For example, a self-employed borrower will always need to provide tax returns and financial statements, but until the lender knows the borrower is self-employed, it cannot know to ask for these items. However, there are some useful generalizations:

• The loan application process is essentially like taking a photograph of your finances; it is to your benefit to hold still for the picture. So, try to avoid moving money from one account to another; e.g., if you plan to open a new bank account here, wait until after you have applied for the loan, when you can  discuss any plans of moving accounts with your lender. Also, any new debts incurred after the application could cause an approval to be withdrawn.
•  If you are about to move, try to pack anything that even looks like it might have something to do with your finances (what you make, have, and owe), into one place.
•  Try to have the names and addresses of your rental agent(s) and / or lender(s) for your residence(s) during the two years prior to the new loan application.
• You can save a lot of time if you have the last three months' statements for any asset account - such as checking, savings, mutual funds, IRAs, stocks, etc. If you don't have these, then bring whatever you can find in the way of statements - but always have the account numbers if at all possible.
•  Always try to have the account numbers for all current debts, for any mortgage loan from the last two years, and for any debts recently paid out.
•  If you are self-employed, or receive much income from commissions, tips, etc., then you will need the last two years' tax returns. If you own 25% of any corporation or partnership, then the returns for that / those corporation(s) will be almost always necessary.
• If you are not self-employed, then the most recent month's consecutive paystubs (3 if paid bi-weekly, 5, if weekly). Also, even though it may not be necessary, it is always a good idea to have your last two years' tax returns on hand, since there are circumstances, such as having rental income, when these forms are needed for proper verification.
•  If you plan to obtain a VA loan, then bring your Certificate of Eligibility, if you have it. If you do not have this form, then it could help you to get one ahead of time (See form and instructions in this package.).
•  Almost certainly, no matter how hard you try, the lender will ask for something you didn't bring, so, be prepared for that.