# WP20 cost schedule — every parameter carries a `source` (verified public figure) or is labelled `assumption`
# (author assumption with the sensitivity range used in Experiments 7–8 and the Monte Carlo of Experiment 14).
# Currency: CAD. Base valuation date: 2026-Q2 (listing window 2026-08 → 2026-10).
version: 1.0
valuation_quarter: "2026-04-01"      # StatCan refPer label for 2026-Q2

rcn:
  # Two published anchors for the per-area cost of a new single-family house. Anchor B (Québec, 2026) is the headline
  # because it is province- and date-specific; anchor A (Altus, Montréal hard costs) is reported as a lower-bound alternative.
  anchor_default: B
  anchors:
    A:
      label: "Altus Group 2026 Canadian Cost Guide, Montréal hard construction cost (via NerdWallet Canada), $155–215/sq ft, single-family with unfinished basement"
      reference_storeys: "1"                      # band not storey-specific; treated as the one-storey reference (assumption)
      reference_quarter: "2026-01-01"
      grade_per_sqft: {basic: 155, standard: 175, upgraded: 195, luxury: 230}
      grade_sensitivity_per_sqft: {basic: [140, 170], standard: [160, 195], upgraded: [180, 215], luxury: [205, 280]}
      storey_multiplier: {"1": 1.00, "1.5": 0.97, "2": 0.93, "2.5": 0.92, "3": 0.92}   # assumption
    B:
      label: "Québec industry guides 2026 (Soumission Rénovation, updated 2026-08-31, citing SHQ 2026 data: standard finish $280–325/sq ft, cottage with unfinished basement $230–285, high-end $350+; Dessins Drummond, updated 2026-09-24: $260–350/sq ft, cottage ≈ $280, bungalow ≈ $345); excludes land, servicing, soil tests, professional fees, landscaping"
      reference_storeys: "2"                      # the quoted standard band describes a two-storey 'cottage'
      reference_quarter: "2026-07-01"             # treated as current (no BCPI beyond 2026-Q2; factor 1)
      grade_per_sqft: {basic: 257, standard: 302, upgraded: 340, luxury: 400}
      grade_sensitivity_per_sqft: {basic: [230, 285], standard: [280, 325], upgraded: [325, 375], luxury: [350, 450]}
      # bungalow ≈ cottage + $100/sq ft (Soumission Rénovation) and 345 vs 280 (Dessins Drummond) → one-storey ≈ 1.25× two-storey
      storey_multiplier: {"1": 1.25, "1.5": 1.12, "2": 1.00, "2.5": 0.97, "3": 0.97}
  # Legacy single-anchor fields (kept for reference; the model reads `anchors`)
  # Hard construction cost per square foot, single-family house with unfinished basement, excluding land, Montréal,
  # Altus Group 2026 Canadian Cost Guide as tabulated by NerdWallet Canada (secondary source; see docs/institutional_sources.md).
  base_band_per_sqft_montreal: {low: 155, high: 215}
  base_band_source: "Altus Group, 2026 Canadian Cost Guide, via NerdWallet Canada table (accessed 2026-10-20); secondary source"
  base_band_reference_quarter: "2026-01-01"       # guide published 2026-04-23; costs taken as early-2026 (assumption)
  # Finish-grade mapping onto the band (assumption: linear placement within the published band; luxury may exceed it)
  grade_per_sqft: {basic: 155, standard: 175, upgraded: 195, luxury: 230}
  grade_sensitivity_per_sqft: {basic: [140, 170], standard: [160, 195], upgraded: [180, 215], luxury: [205, 280]}
  # Storey multiplier on per-area cost (assumption: foundation and roof are spread over more floor area in taller houses)
  storey_multiplier: {"1": 1.00, "1.5": 0.97, "2": 0.93, "2.5": 0.92, "3": 0.92}
  storey_multiplier_sensitivity: 0.03
  # Party-wall adjustment for attached houses (assumption)
  attached_multiplier: {detached: 1.00, semi_detached: 0.97, row_or_townhouse: 0.94}
  # Add-ons (assumptions, CAD, 2026) — sensitivity ±30 %
  basement_finish_per_sqft: {finished: 45, partially_finished: 22, unfinished: 0}
  garage: {attached: 35000, detached: 45000, carport: 8000, none_visible: 0, none: 0}
  add_on_sensitivity: 0.30
  # Indirect (soft) costs and entrepreneurial incentive on top of hard costs (assumptions; standard cost-approach components)
  soft_cost_share: 0.10
  soft_cost_sensitivity: [0.05, 0.15]
  entrepreneurial_incentive: 0.08
  entrepreneurial_incentive_sensitivity: [0.0, 0.15]

site_improvements:
  baseline_share_of_rcn: 0.02           # driveway, landscaping, fences (assumption; sensitivity 0–4 %)
  pool: {inground: 60000, above_ground: 8000, none: 0}   # assumption, text-claimed only; sensitivity ±40 %

temporal_regional:
  # Statistics Canada table 18-10-0289-01, single-detached house, division composite, 2023 = 100 (data/raw/statcan/)
  statcan_vectors: {montreal: 1617911556, quebec: 1617911172, gatineau: 1617912324, composite: 1617908100}
  cma_to_series: {montreal: montreal, quebec: quebec, gatineau: gatineau, sherbrooke: composite, trois-rivieres: composite, saguenay: composite, other: composite}
  # Cross-CMA cost LEVEL is not published for Québec City; baseline assumes the Montréal level everywhere
  # (regional_level_factor = 1.0) and Experiment 7 varies it in [0.90, 1.10] and under the "relative growth since 2023" scenario.
  regional_level_factor: 1.0
  regional_level_sensitivity: [0.90, 1.10]
  # Dessins Drummond (2026): building in Montréal or Québec City costs 10–25 % more than in other regions → scenario
  non_metro_discount_scenario: {metro_cmas: [montreal, quebec, gatineau], factor_other: 0.85}

depreciation:
  method: "straight-line age–life with condition-adjusted effective age (physical); functional and external = 0 in baseline"
  economic_life_years: 60
  economic_life_sensitivity: [50, 75]
  max_physical: 0.85
  # effective age = chronological age × condition factor (composite 1–5 condition score; 3 = average → factor 1)
  condition_factor: {1: 1.40, 2: 1.20, 3: 1.00, 4: 0.75, 5: 0.55}
  condition_factor_strength_sensitivity: [0.5, 1.5]    # scales the deviation of the factor from 1
  renovation_extensive_years_removed: 10
  renovation_partial_years_removed: 4
  min_effective_age: 1
  external_obsolescence_scenario: 0.10

land:
  source: "assessment roll land value (valeur_terrain) at the roll market-condition date (LFM art. 46)"
  index: "Vrai Prix monthly single-family price index (market_index, type unifamilial) from roll date month to 2026-07"
  index_share_applied: 1.0            # baseline: full indexing; sensitivity {0.0, 0.5, 1.0} (land vs house price growth differ)

benchmarks:
  assessor_building_value_index: "StatCan BCPI single-detached, CMA series, from roll market date quarter to 2026-Q2"

baselines:
  B0: {grade: standard, condition: 3, basement: unfinished, garage: none, pool: none, attached: from_listing_type}