When you are offered a "rate lock" from a lender, it means that you are guaranteed to keep a certain interest rate for a determined period for the application process. This saves you from working through your entire application process and finding out at the end that your interest rate has gone up.
Rate lock periods can be various lengths of time, anywhere from 15 to 60 days, with the longer ones usually costing more. You can get a longer period for your lock, but in making this choice, will most likely have a higher rate than you would with a shorter span of time
There are more ways to get a better rate, besides choosing a shorter rate lock period. A bigger down payment will give you a reduced interest rate, since you will be starting out with more equity. You can pay points to lower your interest rate for the loan term, meaning you pay more up front. To a lot of people, this makes sense and is a good deal..
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