Because South Lyon's housing runs newer than the oldest pockets of the broader service area, the parts that come up most here are torsion springs sized for post-1980s steel sectional doors, standard-width end bearing plates, and opener circuit boards or logic modules for chain and belt drives from that generation rather than the older screw-drive units.
We don't stock obsolete one-piece door hardware on the truck for South Lyon runs the way we might for an older neighborhood closer to Novi - it's just not what the housing calls for here, and carrying dead stock doesn't help you. If your door turns out to be an outlier - something custom-installed well outside what the build era suggests - that's the one case where we may need to order a part and come back, and we'd rather tell you that than guess on site.
Cables, rollers, and standard steel hinges we carry regardless of the house's age, since those wear out on a schedule tied to use, not construction year.