Subsidence survey cost: Subsidence Report Fee Index

Every row is a verbatim sentence read from the named source's own page through our fetch service on the date shown, hash-pinned to the stored read (the sha of the page's visible text; the raw page is mirrored to R2).

17 of the 9 named sources that could be read published a usable figure; 5 published none and are recorded as not published, never filled in; 86 could not be read (blocked, dead or unreachable) and count nowhere.

The headline figures (median, minimum, maximum, quartiles) are over ONE figure per source for each breakdown it prices, in GBP (a source's median where its page yielded several accepted sentences for one breakdown), so a page that gives figures for several breakdowns gives one for each and N counts 19 figures, never sentences; 892 candidate sentence(s) were refused by a reviewer with the reason recorded.

The fuller derivation this dataset is chartered to grow into (not yet what the figures above are; they are each source's own published figure as read): one row per provider per PRODUCT - because 'subsidence survey' is six priced things and the buyer does not yet know which he needs - carrying the published price or range, whether it is a from-price, a banded ladder or a per-visit rate, whether VAT is stated, and the region.

Across those rows the figures nobody publishes: the median, minimum and maximum published price per product and per region; the full cost of the whole investigation path a real case runs (engineer's report, then drains, then trees, then monitoring, then trial pits) against the single number the buyer searched for; the share of providers publishing a price at all, by product - which the harvest shows is far higher for drainage and arboriculture than for structural engineering; whether VAT is included, which moves a quoted £275 to £330; and repriced-since the previous read

892 candidate sentences on these pages were refused by a reviewer; each refusal and its reason is recorded in the review ledger.