A rate "lock" or "commitment" is a promise from the lender to freeze a specific interest rate and a particular number of points for you for a specified period of time while your application is processed. This means your interest rate can't go up as you are working through the application process.
While there are several lengths of rate lock periods (from 15 to 60 days), the longer ones are usually more expensive. You can get a longer period for your lock, but in making this choice, will likely have a higher rate than you would with a shorter rate lock span of time
In addition to opting for the shorter lock period, there are several ways you may be able to score the best rate. A larger down payment will get you a better interest rate, since you're starting out with more equity. You could choose to pay points to lower your interest rate over the loan term, meaning you pay more up front. One strategy that is a good option for many people is to pay points to bring the rate down over the term of the loan. You'll pay more initially, but you'll save money, especially if you keep the loan for the full term.
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