For an install, we carry a working range of standard door widths and both steel and composite panel options, along with the track, spring, and opener hardware to match. What we don't carry is a custom-order door already built for a nonstandard opening - those get ordered once we've measured, and that's a lead time we're upfront about rather than promising same-day on something we can't stock. Given how many openings on this side of town were framed decades before current door sizing became standard, we measure twice before we order anything nonstandard, because a wrong order means another 40-mile round trip from the shop for both of us. The truck stock covers most jobs in one visit. Anything custom gets flagged at the estimate, not discovered at install.