{"model":"equipment-lease-vs-buy","specVersion":"1.0.0","specUrl":"/api/v1/models/equipment-lease-vs-buy/spec","inputs":{"equipmentCost":{"kind":"float","min":5000,"max":5000000},"loanRate":{"kind":"float","min":0.02,"max":0.25},"loanTermMonths":{"kind":"int","min":12,"max":84},"monthlyLeasePayment":{"kind":"float","min":100,"max":100000},"leaseTermMonths":{"kind":"int","min":12,"max":84},"residualValuePct":{"kind":"float","min":0,"max":0.6},"marginalTaxRate":{"kind":"float","min":0,"max":0.37}},"arrayInputs":{},"constraints":["Costs are after-tax lifetime nominal dollars, undiscounted, and the two terms may differ — the loan-comparison time-value caveat applies. Straight-line depreciation to residual; accelerated schedules (MACRS/§179/bonus) excluded.","Under this contract the tax rate rescales BOTH costs by (1 − marginalTaxRate) and can never change cheaperOption — taxes flip the real decision only through deduction timing and discounting, which are excluded (see spec)."],"sentinels":[],"facts":[],"disclaimer":"Illustrative planning model, not financial advice. Outputs follow the published model spec exactly; read the spec for assumptions and exclusions before relying on any number."}