When you are offered a "rate lock" from your lender, it means that you are guaranteed to get a set interest rate over a certain number of days while you work on your application process. This means your interest rate won't rise as you are working through the application process.
Rate lock periods can be various lengths of time, between fifteen to sixty days, with the longer ones typically costing more. You can get a longer period for your lock, but in doing so, will likely have a higher interest rate than you would have with a shorter rate lock span of time
There are other ways to get a lower rate, in addition to going with a shorter rate lock period. The more the down payment, the smaller the rate will be, as you will be starting with more equity. You may choose to pay points to improve your interest rate for the loan term, meaning you pay more up front. One strategy that is a good option for many people is to pay points to reduce the interest rate over the term of the loan. You'll pay more initially, but you'll save money in the long run.
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