Depending on whether you are considering a purchase or a refinance will make a big difference. As stated earlier, most mortgage brokers have systems that facilitate tracking available mortgage rates & products for customers. What's more important is finding a broker that you trust and like. You may want to narrow your list down by requesting a 'Good Faith Estimate' that will define the various expenses related to their lending programs. That means you'll want to have a maximum purchase price in mind and a pre-approval for the necessary mortgage you'll require. In this way, you'll have a better idea who is offering you a fair (if not best) deal for your transaction. You can consult with your realtor or family and friends who might be able to recommend someone.
On the possibility that you are looking to refinance an existing mortgage, you may want to do a bit more research regarding your home's current market value. Many owners who acquired property in the past 3 or 4 years are finding that the current market value of their home is not different from the original purchase price and quite possibly lower. In that case, you must consider whether you put more than 20% down (or more) at the time of purchase. If not, then you run the risk that your equity is not 20% or greater. That may make a refinance not economically attractive since you might be required to purchase PMI (premium mortgage insurance). A lot will depend on the spread between your current mortgage rate and the 4.5% rate you desire. If you've had PMI all along then it may be worth it. The best person to make this determination is a mortgage broker.
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