Our mortgage loan prequalifications(preapprovals under HMDA) will now have a "Committment Fee" of $50. It is not an application fee (nor do we charge one) since it will only be for those who ask to be prequalified and have a committment issued. (Apparently realtors in our area are asking that their clients get prequalified before they do a lot or before an offer is made on real estate.) This will entice them to come back to us when they are ready for their mortgage instead of going to another lender. What we plan to do is tell customers we will subtract this $50 "committment fee" from the $150 "underwriting fee" that we normally charge (we would list the $50 as POC on the HUD). Can anyone out there help me think of potential problems with this?

Sounds ok to me. Be sure both the underwriting and the committment fee end up in the prepaid finance charge calculation.