A straight swap - same opening, same width, sound header - is the fast version of this job: measure, remove the old door, set the new track and springs, hang the panel, balance it. Add a header repair, a non-standard width panel, or an opener upgrade with new wiring, and the timeline stretches because you're waiting on a carpenter's schedule or a special-order panel rather than on us.
On houses from the 1970s in this town, we plan for the possibility of that extra step rather than promise a single number up front. We'll tell you at the time of the estimate whether your opening looks like a same-day job or a two-visit job - one to confirm the framing is ready, one to install. We're not based in Solana Beach itself; we come over from Encinitas, about four miles up the coast, so scheduling is a matter of booking the visit rather than a walk-in same-hour call.