Car TCO Skill

Cars are sold on monthly payments and owned on total cost — and the two rank options differently. Depreciation (the biggest cost of a new car) never appears on a statement; maintenance (the biggest fear about an old car) is usually smaller than a year of new-car depreciation. This skill compares buy-new, buy-used, lease-forever, and keep-current on the same total-cost basis over the same horizon.

What This Skill Produces

• Ranked scenario totals — every requested scenario over the same horizon, cheapest first
• True per-month cost — total ÷ months, the number to compare against the payment the dealer quotes
• The assumption ledger — depreciation curve, maintenance ramp, insurance deltas, all labeled
• The not-modeled list — financing interest, jurisdiction taxes, reliability luck

Required Inputs

Ask for these if not provided:

• Which scenarios to compare — any of: new price, used-equivalent price, lease terms, current car's value + annual maintenance
• Horizon — years they realistically keep cars (default 8, labeled); short horizons flatter leasing, long ones flatter buying
• Miles per year and rough fuel/energy cost (defaults 12,000 mi / $0.14 per mile, labeled)

Programmatic Helper