Know your credit score before you begin looking for a loan. If you can, try to remove any blemishes from your credit report before applying for a refinance.
Carefully review the estimated closing costs. If you decide to lock in the rate, the lender will send you a "good faith estimate" of your closing costs within three days. Go over the numbers carefully, and compare them to the ones that appear on the final settlement statement (the HUD-1) from your previous mortgage.
Lenders like pristine credit reports. If you have a bunch of open credit card accounts that you never use (and who doesn't?), consider closing them. It will boost your credit score and make you a much more attractive borrower to a lender. Then, a month after you've closed your accounts, go over your credit report with a fine-tooth comb. It should read that the accounts were closed at your request. (You don't want lenders to think someone cut you off and that you're a bad credit risk.)
Unless you are getting a lower interest rate, refinancing your home may cost you more money in the long run and may require you to pay higher monthly payments.
If you have equity built up in your home, and you need cash, you have two choices: get a home equity loan or utilize cash-out refinancing. Each has its pros and cons, so be sure to evaluate your situation carefully prior to making a decision.