For a broken torsion spring, we match the spring to the door's weight and cycle rating rather than grabbing whatever's closest - undersized springs are a big reason people end up calling twice in one year. We check cables, drums, and bearing plates at the same time, since a spring failure often takes a cable partway with it.
For opener issues, we test the logic board, the trolley, and the safety sensors before replacing anything, because a sensor that's just dirty or knocked out of alignment gets misdiagnosed as a dead board more than it should. Track and roller work is straightforward: realign bent track, swap worn rollers, and check that the door is still square to the frame once it's done.
One limit worth saying plainly: if a door's track is badly bent or the panels are rusted through, repair is a patch, not a fix. On a door that old, replacement is usually the better money.