This was a small job, no doubt, but I was able to save the customer almost $200 in the process!  He wished to have his garage entry door replaced because the lockset/deadbolt was extremely outdated, plus the door was too tight in the jamb.  I purchased a new wood door just in case, but I really thought I could install a new lockset without even removing the door.  I removed the old hardware, and filled the void with a 5/8″ piece of hardwood to create a good solid structure for the new hardware.  To ease the tight fit, I used a wood plane to remove about 1/8″ from the edge of the door.  Problem solved, and I saved him cost of a new door ($54.99) as well as 4 extra hours labor ($120).  This spring, he will fill the small holes, touch up the paint job, and be good to go!  HAPPY CUSTOMER!