1971 build determines failure mode
In SeaTac, the median home was built around 1971, a good decade or more ahead of the 1984 median across the rest of the areas we cover out of Renton. That gap matters. A door installed in the early 1970s is more likely to be running on a plain steel track with rollers that have never been swapped, bent by a car bumper or knocked loose by a slipped cable.