Call and tell us what the door is doing - won't open, hangs crooked, or dropped on one side with a bang. That's usually enough for us to know whether it's a snapped cable, a cable off the drum, or something worse like a bent track pulling the cable sideways. We ask for the door's age and whether it's a single or double door, since cable size and drum setup differ between the two.
We don't quote a cable repair over the phone without seeing the door. A cable that's frayed but holding can look fine from across the garage and still be a day away from letting go. We'd rather look at the drums, the bottom brackets, and the spring before we tell you what it'll take.
One thing we're upfront about: if the cable failure happened because a spring let go first, you're looking at a spring-and-cable job, not a cable-only fix. We'll tell you that before we start, not after.