If you want to lock in the lowest rate possible, it's usually a good idea to receive several loan estimates. The best estimate can be used to bargain with other lenders, which might lead to a cheaper interest rate or a reduction in some administrative costs. Ask about any discounts, such as appraisal waivers, that might be available to you when you're comparison shopping. Customers of certain banking institutions may receive discounts, and there may also be military discounts available.