Door repairs vary depending on the type of damage. You can plug holes up to a half-inch wide with wood putty or two coats of auto body filler. It should first dry and then get smoothed out before painting. Removing ⅛-inch off the edge of a door in an existing frame starts at around $15. It might cost between $100 and $1,000, depending on whether you need to replace or reframe the old door.