We carry standard torsion springs sized for residential doors, standard-gauge lift cable, rollers, and the hardware for track realignment on most calls. What we don't always carry is legacy bracket hardware specific to 1960s-era installs - some of those mounting plates were never standardized the way modern track hardware is, and on a handful of jobs we've had to measure on site and come back with the right part rather than guess.
That's the one honest limit on same-visit repairs here: if your house still has original mounting hardware from 1962, there's a real chance the first visit is diagnosis and measurement, and the second is the fix. We'd rather tell you that before the truck leaves Ashburn than have you wait around for a part we didn't confirm.