Cost Browser in OpenConstructionERP

The cost database (2026)

Eight national bases (78,228 positions) plus 30 global markets, each in the 95-column CWICR master schema, with 26 language editions and 48 PPP-repriced resource catalogs per national base.

Browsing paths

Path	Endpoint	Purpose
Base picker	GET /api/v1/costs/base-catalog	list families, variants, currencies, positions, loaded badge
List / search	GET /api/v1/costs/?region=...&q=...&limit=...	SQL keyword search (works without Qdrant)
Tree	GET /api/v1/costs/category-tree/?region=...	collection → department → section → subsection → category
Item detail	GET /api/v1/costs/{id}	full components[] breakdown + metadata + variants
Autocomplete	GET /api/v1/costs/autocomplete?q=...	fast typeahead for the BOQ editor
Semantic	/qdrant-search (Qdrant)	BGE-M3 multilingual ranking across cwicr_<lang>_v3 collections

Classification tree

Every item carries classification{} built from the parquet:

collection (source, e.g. "İnşaat")
 └─ department (discipline, e.g. "İnşaat")
     └─ section (chapter, e.g. "LAVABOLAR")
         └─ subsection
             └─ category (normalized type, e.g. "CONSTRUCTION WORK")

Chinese positions may show partial classification (source scope) — that is honest, not a bug.

Certainty & variants

• Some items carry abstract-resource variants (e.g. concrete grade pickers): the item detail exposes variants[] with per-variant prices; picking one replaces the BOQ line description/price.
• certainty badges grade how confidently an item matches a BIM element — review low-certainty picks.

Resource catalog

The catalog module stores the compact per-market catalogs (resource_code, name, type, category, unit, price_avg/min/max, currency, usage_count, classification under specifications). Coefficient bases (VN, ID) seed an editable resource price sheet here — that is how they become estimable.

Best practices

1. Always filter by region — the same code exists in several bases with different prices.
2. Trust the tree over free-text for browsing; use free-text for finding.
3. Treat rate = 0 on VN/ID as "not yet priced", not as free work.