Rebuild-cost proxy: county permit valuation per unit trended by construction PPI (estimate, labeled proxy)

Single-family rebuild proxy for buyer, owner and lender agents: Census permit value per unit (Building Permits Survey) plus BLS construction-input PPI since that year, as a $/sq ft range for a stated size, floored at FEMA $100. National labeled proxy, not a coverage amount or adequacy verdict. Permit values understate cost. Use this when you can call Locus free tools (REST tools/call or MCP). Use locus-rebuild-cost-context instead when your client can only call paid x402 routes; it returns the same records. Direct flat-body route for this one free resource; no API key, payment, or catalog wrapper. Return only the cited bounded evidence described here; this route never produces a paid brief or full report.