Q99. We want to apply for a home equity line of credit. The bank says it has to know what your house is worth (It has to be worth a certain amount over what we still owe on the mortgage to get a loan at a good rate). A loan at a bad rate will cost $10,000 more than a loan at a good rate. We think there is a 60:40 chance that our house is in fact worth enough to get a good rate. We have a choice between a cheap appraisal ($100) and an expensive appraisal ($1000). A cheap appraisal, we have learned, has a 40% chance of correctly valuing a property. An expensive appraisal is right 70% of the time. Draw a decision tree that will help us figure out what to do.