A rate "lock" or "commitment" is a lender's promise to set a particular interest rate and a specific number of points for you for a certain period during your application process. This ensures that your interest rate won't go up during the application process.
Although there are several lengths of rate lock periods (from 15 to 60 days), the extended spans are generally more expensive. You can get a longer period for your lock, but in doing so, will likely have a higher rate than you would with a shorter span of time
In addition to opting for the shorter lock period, there are other ways you are able to score the best rate. The larger the down payment, the better your rate will be, since you will be entering the loan with more equity. You may opt to pay points to reduce your interest rate over the loan term, meaning you pay more initially. For many people, this makes sense and is a good deal..
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