When you're offered a "rate lock" from your lender, it means that you are guaranteed to get a certain interest rate for a certain number of days while you work on your application process. This means your interest rate cannot go up during the application process.
Rate lock periods can be various lengths of time, between fifteen to sixty days, with the longer spans generally costing more. You can get a longer period for your lock, but in choosing this option, will most likely have a higher interest rate than you would have with a shorter rate lock span of time
There are more ways to get a reduced rate, in addition to going with a shorter rate lock period. The more the down payment, the smaller the interest rate will be, as you will have more equity from the start. You can pay points to improve your interest rate over the term of the loan, meaning you pay more initially. One strategy that is a good option for some is to pay points to improve the interest rate over the term of the loan. You'll pay more initially, but you'll come out ahead in the end.
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