Resources

22 resources

Short, specific explainers for the concepts behind the calculators. Each one answers a real question that comes up before or after running a specific engine. SeeMethodology for how the underlying math works.

• Why Monthly Payment Is Not True Vehicle Cost
  The monthly payment answers one question, term length and financing structure can hide the real cost of owning a car.
• How Auto Loan APR, Interest Rate, and Fees Differ
  APR, interest rate, and fees are three different numbers on the same loan offer, and dealers rarely explain how they relate.
• Repair vs Replace Framework
  A framework for the actual decision behind a repair estimate, not just whether one repair bill feels too big.
• How to Compare New vs Used on Total Cost
  A used car's lower price and a new car's lower repair risk both have to be converted into the same total-cost number before "new or used" has a real answer.
• What Negative Equity Actually Means
  Owing more than a car is worth changes what your options actually are, not just what your next payment looks like.
• Auto Loan Term Length: What 48 vs 84 Months Actually Costs You
  A longer term almost always lowers the payment. It also almost always raises total interest and delays the point you owe less than the car is worth.
• Cash, Down Payment, or Financing: The Real Comparison
  Paying cash guarantees you avoid interest. Investing instead bets on a return beating that rate. Here is how to actually compare them, with a live calculator.
• How to Estimate Cost Per Mile Correctly
  A per-mile figure is only honest if it includes fixed costs, not just gas and tires.
• Trade-In Value vs Trade-In Equity
  The number a dealer offers for your trade is not the number that actually reduces your next deal.
• Negative Equity Rollover: What Riding Along Actually Costs
  Rolling a trade-in shortfall into a new loan does not erase it, it finances it at the new rate for the new term. A live calculator for what that actually adds.
• Auto Loan Refinancing: When It Actually Pays Off
  A lower rate is not automatically a win once fees and term resets are counted. Here is the real break-even question, with a live calculator.
• How to Estimate Maintenance and Repair Assumptions
  Maintenance and repair costs are the input every ownership calculator depends on most, and the one people guess at loosest.
• Solving for the Auto Loan Number You Actually Need
  Most real loan questions run backward from what a standard calculator answers. Find the right reverse-engine for your specific question.
• Trade Timing: Why "Wait a Few Months" Isn't Free
  Value and loan balance both move every month, but not always in the direction that helps you. A live projection of your own value and payoff curves.
• Proactive Vehicle Replacement Timing
  Most replacement decisions get made by a repair bill, reactively. A live year-by-year sweep for the cheapest switch point if nothing breaks.
• Lease Money Factor and Residual Value Explained
  A lease payment is built from two numbers dealers rarely explain clearly: the money factor and the residual value.
• The Lease-End Decision: Buyout, Return, or Extend
  Buying out, returning, extending, and comparing against a used car are four different comparisons. An interactive walkthrough to the right one.
• Lease Mileage Overage and Early Exit Costs
  A lease payment assumes a mileage allowance and a full term. Going over either has its own separate, specific penalty math.
• Choosing the Right EV, Hybrid, or Gas Comparison
  EV-vs-gas, EV-vs-hybrid, and hybrid-vs-gas are different comparisons with different cost drivers, even though they share the same total-cost model.
• EV Charging Cost Methodology
  EV charging cost depends on your home/public mix and charging losses, not just a single electricity rate.
• EV and Hybrid Break-Even: Three Different Questions
  Break-even mileage, break-even premium, and break-even fuel price are three different thresholds. A live simulation of the underlying tradeoff, plus which engine answers which.
• Home Charger Economics: Install vs Public Charging
  A home charger shifts more charging to the cheaper rate, but it is an upfront cost with its own payback period, not a free win. A live payback calculator.