Most calls fall into a short list: a torsion spring that's let go, a cable that's frayed or snapped, rollers that have worn out of their track, or an opener that's stopped responding to the remote or the wall button. Cold winters put real stress on springs and cables here, since metal fatigues faster with repeated temperature swings, and that shows up most in doors that are already a decade or two old.
We also get called for doors that have come off track entirely, usually after something hits a roller or a panel takes a hit. Those jobs need an in-person look before any price gets quoted, because the fix ranges from a $120 roller swap to a full track and panel replacement depending on what's bent and how badly.
What we try not to do is sell a repair when the door's not worth repairing. If a door built decades ago needs a new opener, new springs, and new panels all at once, we'll say so and let you decide whether that adds up to more than a replacement door would cost.