Time it takes: 30 minutesOnly now are many borrowers with risky loans finding that they misunderstood the terms. First pull out the one-page Truth in Lending Disclosure your lender gave you: The APR on it is the best estimate of what you are paying. Lower rates mentioned in other loan documents are likely come-on offers. If your rate is variable, scan the adjustable-rate disclosures section of your mortgage for the date it changes and the highest it can go. Examine every page for the words "prepayment penalty."