Locking the price of a mortgage is full of potential problems for the unwary borrower.

This decision is especially problematic in today's market because prices can jump around from day to day, and lenders take much longer than in pre-crisis years to approve an application, and often can't.

Locking means that the lender commits that the price at closing will be the lock price, even if the market price is higher at closing than it was on the lock date. The price commitment holds for a specified period, usually 30 to 90 days, with longer periods priced higher. Whether the borrower is equally committed if the price at closing is lower depends on the lender's policy.

Last year I wrote an article on one approach a borrower could take to avoid lock problems, which is to entrust the process to a mortgage broker who knows exactly what the problems are. The drawback is the difficulty of assuring that the broker will use his knowledge for the benefit of the borrower rather than himself.

This article is about how borrowers can protect themselves when they deal directly with lenders. The key is in knowing the lender's locking rules and procedures beforehand. This is not easy because very few volunteer the information; the borrower must ask.

Upfront mortgage lenders (UMLs) are an exception because one of my requirements for certification is that they show their lock policies on their web sites. In reviewing these policies recently, however, I found wide discrepancies in completeness, which is my fault; my disclosure rules were too vague. This is being remedied, and very shortly the UMLs will have revised lock statements that are responsive to the questions listed below.