It is feasible to go for a refinance when you have built up at least 10% equity in your home (For Fannie Mae owned mortgages, the value is 5%). It is also possible for you to choose the option if your equity is less than 5%, but you may have to pay a certain amount of cash in order to make up for the difference in equity.
Ask for more than just rates. Bad loan officers will tell you anything to keep you on the phone -- then change the details to suit them later. Instead, make them get real with you! Ask how long they've been in the industry. Probe them about their experience in the industry. Also, ask what their opinion is on the current market and where it's going.
Be specific about the loan you want. The more precise you are, the easier it will be for a loan officer or mortgage broker to find the best rate. For example, do you want a 15-year or 30-year mortgage? Do you need a "jumbo" mortgage (more than $333,700)? Are you willing to pay points to reduce the interest rate? The answers to these questions will depend on several factors, including when you plan to sell the house and how soon you want to retire your debt. Only you know the answers, but the sooner you know them, the better.
Be Ready. After your loan is approved, you'll need to sign your loan documents and provide a check for any out-of-pocket closing costs. Make sure the funds are available in your account, and be ready to make room in your schedule to read and sign your loan documents as soon as possible.