How to use: Calculate monthly payments and total cost for vehicle financing. Enter Loan Amount (vehicle price minus down payment, typically $15,000-$40,000), Down Payment (upfront cash - typically 10-20% of price), Interest Rate (APR from lender - typically 3-8% for good credit), and Loan Term (years - typically 3, 4, 5, or 6 years). Results show: Monthly Payment (amount due each month), Total Interest (extra cost beyond principal), and Total Cost (loan amount + interest). Example: $25,000 loan, $5,000 down, 5.5% APR, 5 years = $382/month, $2,920 interest, $27,920 total. Longer terms = lower monthly payment but higher total interest. Aim for 20% down, 4-year term max, payment <15% of monthly income. Critical for auto loan shopping and affordability analysis.