We come out from Charlotte for this, about 14 miles each way, so we build the drive into how we schedule the day rather than promising a same-hour arrival we can't back up from that distance. Once we're on site, cable replacement on a standard torsion-spring double door is a contained job: release tension on the springs safely, pull the old cables off the drums, run new ones matched to the door's weight and track length, and reset the drum tension so the door travels level on both sides.
We check the drums and the bottom brackets while we're in there, since a cable that's frayed from age often has a drum edge or a bracket that caused the wear in the first place. Replacing the cable without addressing that just buys you the same failure again in a year or two.
We carry standard cable stock for common residential door weights and heights, which covers most of what's out on doors from the late 1990s and 2000s. If a door has a nonstandard track configuration or an unusual spring setup, that can mean a return trip once we've confirmed the part. We'd rather tell you that up front than guess at it on the driveway.