Car Budget Calculator
function calculateCarBudget() {
var income = parseFloat(document.getElementById('monthlyIncome').value);
var expenses = parseFloat(document.getElementById('monthlyExpenses').value);
var savings = parseFloat(document.getElementById('savingsGoal').value);
var downPayment = parseFloat(document.getElementById('downPayment').value) || 0;
var runningCosts = parseFloat(document.getElementById('fuelInsurance').value) || 0;
var resultsArea = document.getElementById('resultsArea');
var maxPriceDisp = document.getElementById('maxPriceResult');
var monthlyDisp = document.getElementById('monthlyPaymentResult');
var warningDisp = document.getElementById('budgetWarning');
if (isNaN(income) || isNaN(expenses) || isNaN(savings)) {
alert("Please enter valid numbers for income, expenses, and savings goals.");
return;
}
// Calculation Logic
// 1. Calculate strictly available cash after priorities
var hardLimit = income – expenses – savings;
// 2. Financial Rule of Thumb: 10% of monthly income is "Safe", 15% is "Stretching"
var safeMonthlyTotal = income * 0.10;
var maxMonthlyTotal = income * 0.15;
// The payment available is whichever is lower: their hard limit or 15% of income
var potentialPaymentLimit = Math.min(hardLimit, maxMonthlyTotal);
// Deduct running costs (gas/insurance) from the available pool
var netMonthlyPayment = potentialPaymentLimit – runningCosts;
if (netMonthlyPayment (income * 0.12)) {
warningDisp.style.backgroundColor = "#fff3e0";
warningDisp.style.color = "#ef6c00";
warningDisp.innerText = "This budget is aggressive (over 12% of income). Ensure your job security is high and maintenance costs for this price bracket are manageable.";
} else {
warningDisp.style.backgroundColor = "#e8f5e9";
warningDisp.style.color = "#2e7d32";
warningDisp.innerText = "This is a healthy budget. Keeping your total transportation costs under 10-12% of your income is a strong move for your financial future.";
}
// Scroll to results
resultsArea.scrollIntoView({ behavior: 'smooth', block: 'nearest' });
}