Base price listed on purchase agreement (excluding finance charges).
Odometer reading when the defect first appeared.
Registration, towing, rental car fees, etc.
Aftermarket parts or damage not covered by warranty.
Base Vehicle Price:$0.00
+ Incidental Costs:$0.00
– Usage Offset (Deduction):$0.00
– Other Deductions:$0.00
Est. Gross Buyback:$0.00
*Note: This amount is split between paying off your lender (if any) and refunding you.
Understanding the Lemon Law Buyback Calculation
When a vehicle is deemed a "lemon" under state laws (such as the California Song-Beverly Consumer Warranty Act), the manufacturer is typically required to repurchase the vehicle from the consumer. However, this is not a full refund of every dollar spent. The most critical component of this calculation is the Usage Offset (also known as the mileage deduction).
The Golden Formula:
The standard formula used in many jurisdictions, particularly California, is: Usage Deduction = ( (Miles at First Repair – Miles at Delivery) / 120,000 ) × Cash Price
Key Factors in the Calculation
1. Cash Price of Vehicle
This is the price listed in your purchase or lease agreement. It includes the base price of the car plus factory-installed options. It typically excludes finance charges (interest), which are handled separately (usually refunded in full or the loan is paid off).
2. The Mileage Offset (Usage Deduction)
Lemon laws recognize that you drove the vehicle before it became a "lemon." The manufacturer is allowed to deduct a fee for this usage. The formula relies heavily on the 120,000-mile denominator, which represents the expected life of the vehicle for legislative purposes.
Mileage at Delivery: The odometer reading when you drove the car off the lot (usually nearly zero for new cars).
Mileage at First Repair: This is crucial. It is NOT the current mileage. It is the mileage when you first brought the vehicle in for the specific defect that triggered the lemon law claim.
3. Incidental Costs (Collateral Charges)
Consumers are entitled to be reimbursed for expenses related to the lemon vehicle. These can include:
Sales tax and registration fees.
Towing charges.
Rental car expenses incurred while the lemon was in the shop.
Repair costs you paid out of pocket.
Loan Balance vs. Refund Check
The "Gross Buyback Amount" calculated above represents the total liability of the manufacturer. This total is used to pay off two parties:
The Lender: If you have an outstanding loan, the manufacturer pays the remaining balance directly to the bank.
The Consumer: You receive the remainder. If you have positive equity or paid cash, this check goes to you. If you have negative equity (from a trade-in rolled into the loan), it may reduce the final payout.
Disclaimer: This calculator provides an estimate based on standard statutory formulas (primarily California Civil Code Section 1793.2). Lemon laws vary significantly by state. Deductions for aftermarket items, physical damage, or negative equity from trade-ins can complicate the final offer. Always consult with a qualified Lemon Law attorney for an accurate assessment of your specific case.
function calculateBuyback() {
// Get input values
var cashPrice = parseFloat(document.getElementById('cashPrice').value);
var mileagePurchase = parseFloat(document.getElementById('mileagePurchase').value);
var mileageProblem = parseFloat(document.getElementById('mileageProblem').value);
var incidentalCosts = parseFloat(document.getElementById('incidentalCosts').value);
var deductions = parseFloat(document.getElementById('deductions').value);
// Validate inputs – set defaults to 0 if empty or invalid
if (isNaN(cashPrice)) cashPrice = 0;
if (isNaN(mileagePurchase)) mileagePurchase = 0;
if (isNaN(mileageProblem)) mileageProblem = 0;
if (isNaN(incidentalCosts)) incidentalCosts = 0;
if (isNaN(deductions)) deductions = 0;
// Basic Validation
if (cashPrice <= 0) {
alert("Please enter a valid Cash Price for the vehicle.");
return;
}
if (mileageProblem < mileagePurchase) {
alert("Mileage at first repair cannot be lower than mileage at delivery.");
return;
}
// 1. Calculate Mileage Driven before first repair attempt
var milesDriven = mileageProblem – mileagePurchase;
// 2. Calculate Usage Offset Formula: (Miles / 120,000) * Cash Price
// The 120,000 denominator is the standard statutory divisor in CA Lemon Law
var offsetAmount = (milesDriven / 120000) * cashPrice;
// 3. Calculate Total Buyback
// Formula: (Price + Incidentals) – (Offset + Deductions)
var grossBuyback = (cashPrice + incidentalCosts) – (offsetAmount + deductions);
// Ensure result isn't negative (though theoretically possible with high negative equity,
// usually buyback calculates what manufacturer owes)
if (grossBuyback < 0) grossBuyback = 0;
// 4. Update Display
document.getElementById('displayPrice').innerText = formatMoney(cashPrice);
document.getElementById('displayIncidentals').innerText = "+ " + formatMoney(incidentalCosts);
document.getElementById('displayOffset').innerText = "- " + formatMoney(offsetAmount);
document.getElementById('displayDeductions').innerText = "- " + formatMoney(deductions);
document.getElementById('displayTotal').innerText = formatMoney(grossBuyback);
// Show result section
document.getElementById('resultSection').style.display = "block";
}
function formatMoney(amount) {
return "$" + amount.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
}