Pre-qualification strengthens your overall picture as a buyer. When you are prequalified you have more negotiating power with the seller and can save thousands of dollars as a result of being in a better negotiating situation. For sellers, an offer from someone who has pre-qualified is to be preferred over an offer from someone who has never met with a lender and thus has little idea of what might or might not be affordable. More over, sellers are often advised to only accept offers from buyers who are pre-qualified for their home loan.
Many real estate agents will not begin working with you unless you get prequalified. By pre-qualifying you demonstrate to agents that you're serious and that you are able to secure financing. Pre-qualification is free of charge, and does not place you under any obligation.

