rent_vs_buy

ai.senaro/personal-finance · Verify this server

Calculation, not advice. Verify with a professional before acting. Deterministic rent-vs-buy decision model. Given a home price, monthly rent, and mortgage rate, computes the breakeven month (when BUY net worth first equals or exceeds RENT net worth), per-horizon net-worth comparison (years 5, 10, 30 + user horizon), and the full year-by-year cost/wealth series for both paths. Includes carrying costs (property tax, insurance, maintenance, PMI, HOA) on the BUY path and opportunity-cost investing on the RENT path. Optional federal tax benefit model (Tier-3: apply_tax_benefit=true) with TY2025/TY2026 SALT caps, mortgage interest deduction, PMI deductibility, and marginal-excess formula. All assumptions cite primary sources (FHFA, BLS, Harvard JCHS, IRS Pub 936, OBBBA Pub. L. 119-21) and can be overridden. HEAVY tool: use output='summary' (default) for scalar headline or output='inline' for chart series. output='capture' writes the full payload to a file on this server's local disk for the chart-render pipeline; available on the local stdio transport only, and rejected with a structured error on the hosted HTTP transport.