During the mortgage process there are a lot of checks and balances that Underwriting and Processing go through. This is what you need to know to make sure your loan goes smoothly.
I would say these are the top 10 headaches for all parties involved.
a) Don't change jobs or go self-employed
b) Don't inquire for new debt, trade in a car or get new credit cards
c) Pay all bills on time! Even your mortgage if refinancing.
d) Set your money aside for closing and don't touch it.
e) Don't buy new furniture. Wait until after closing
f) Don't co-sign for another person
g) Don't move money around from one account to the next.. Every deposit needs a paper trail!
h) The money for closing needs to be in the form of a WIRE, Cashiers Check or Certified Funds. Rarely does an agent accept personal checks.
i) Make sure you have an unexpired gov't issued photo ID on you at the time of closing
j) Tell your Lender everything as problems arise. They will help you solve the issue. Be truthful.