APR

How much should I expect an apr if the interest rate is 6.12%, and aren't all mortgage loans built the same where there's one figure quoting the interest rate and the other quoting the APR.

It's better for you to speak with a professional. He will give you the exact figures. Maybe, you can compare the quotes with few other companies before getting started with one of them.

Someone might be able to explain the technical side of this better than I can but I will take a stab at it. The apr and the quoted rate are virtually the same but the APR is always slightly higher because it is figured before cost paid by the borrower are subtracted out unless you get a no cost loan which means your rate is slightly higher but you pay no closing cost. Both should always show up on a mortgage "good faith estimate" and a "truth in lending statement". You should not see a big gap between these two rates. For example if they quote a rate of 6.12 the APR should be close to that 6.12 as well. It should not be 7% for example. Also, the APR is always a guess of what your rate will be which is why its called a good faith estimate. You will get your true loan rate at closing but it should not vary much from the quoted rate.

Go to fanniemae or freddymac websites.These are government sites with some great mortgage calculators.