Every Saturday morning, Japan time, we re-check the municipal akiya banks of every town named on the regional briefs, re-verify the resort facts against operator publications, and publish whatever changed. Weeks where nothing changed produce no content, and we consider that a feature.
Sources, in order of trust: the town office's own pages and paper files; the prefectural bank aggregators; operator lift and snowfall reports; then, a long way down, everything else. Nothing enters the property index from a commercial portal, because the entire value of the index is that it watches the inventory the portals ignore.
We hold two rules that cost us content. First: no listing appears here without its original source attached, so you can check our translation against the town's Japanese. Second: no resort, hotel, or agent pays for placement, and when we eventually take advertising it will be labelled as loudly as this sentence.
That is the whole method. It is slower than scraping and smaller than a marketplace, which is precisely the point — the snow country's opportunity is a patience arbitrage, and a weekly cadence is what patience looks like when it publishes.