#rental-property-calculator-container .calc-box {
background: #f9f9f9;
border: 1px solid #e0e0e0;
border-radius: 8px;
padding: 25px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
margin-bottom: 30px;
}
#rental-property-calculator-container .form-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
@media (max-width: 600px) {
#rental-property-calculator-container .form-grid {
grid-template-columns: 1fr;
}
}
#rental-property-calculator-container label {
display: block;
margin-bottom: 5px;
font-weight: 600;
font-size: 0.9em;
color: #555;
}
#rental-property-calculator-container input {
width: 100%;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 1em;
box-sizing: border-box; /* Important for padding */
}
#rental-property-calculator-container .section-title {
grid-column: 1 / -1;
font-size: 1.1em;
font-weight: bold;
color: #2c3e50;
margin-top: 10px;
margin-bottom: 5px;
border-bottom: 2px solid #eee;
padding-bottom: 5px;
}
#rental-property-calculator-container button.calc-btn {
grid-column: 1 / -1;
background-color: #27ae60;
color: white;
border: none;
padding: 15px;
font-size: 1.1em;
font-weight: bold;
border-radius: 4px;
cursor: pointer;
transition: background 0.3s;
margin-top: 10px;
}
#rental-property-calculator-container button.calc-btn:hover {
background-color: #219150;
}
#rental-property-calculator-container .results-box {
display: none;
background: #fff;
border: 1px solid #27ae60;
border-radius: 8px;
padding: 20px;
margin-top: 20px;
}
#rental-property-calculator-container .result-row {
display: flex;
justify-content: space-between;
margin-bottom: 10px;
padding-bottom: 10px;
border-bottom: 1px dashed #eee;
}
#rental-property-calculator-container .result-row:last-child {
border-bottom: none;
}
#rental-property-calculator-container .result-label {
color: #555;
}
#rental-property-calculator-container .result-value {
font-weight: bold;
color: #2c3e50;
}
#rental-property-calculator-container .main-result {
text-align: center;
font-size: 1.4em;
color: #27ae60;
margin-bottom: 20px;
font-weight: 800;
}
#rental-property-calculator-container .error-msg {
color: #c0392b;
text-align: center;
margin-top: 10px;
display: none;
}
#rental-property-calculator-container .article-content h2 {
color: #2c3e50;
margin-top: 30px;
}
#rental-property-calculator-container .article-content p {
margin-bottom: 15px;
}
#rental-property-calculator-container .article-content ul {
margin-bottom: 15px;
padding-left: 20px;
}
function calculateRentalCashFlow() {
// 1. Get Input Values
var price = parseFloat(document.getElementById("rpc_price").value);
var closingCosts = parseFloat(document.getElementById("rpc_closing").value);
var downPercent = parseFloat(document.getElementById("rpc_down_percent").value);
var interestRate = parseFloat(document.getElementById("rpc_rate").value);
var termYears = parseFloat(document.getElementById("rpc_term").value);
var monthlyRent = parseFloat(document.getElementById("rpc_rent").value);
var annualTax = parseFloat(document.getElementById("rpc_tax").value);
var annualInsurance = parseFloat(document.getElementById("rpc_insurance").value);
var monthlyHOA = parseFloat(document.getElementById("rpc_hoa").value);
var maintPercent = parseFloat(document.getElementById("rpc_maint").value);
var vacancyPercent = parseFloat(document.getElementById("rpc_vacancy").value);
// 2. Validation
if (isNaN(price) || isNaN(closingCosts) || isNaN(downPercent) || isNaN(interestRate) ||
isNaN(termYears) || isNaN(monthlyRent) || isNaN(annualTax) || isNaN(annualInsurance)) {
document.getElementById("rpc_error").style.display = "block";
document.getElementById("rpc_results").style.display = "none";
return;
}
document.getElementById("rpc_error").style.display = "none";
// 3. Calculation Logic
// Initial Capital
var downPaymentAmount = price * (downPercent / 100);
var totalCashToClose = downPaymentAmount + closingCosts;
var loanAmount = price – downPaymentAmount;
// Mortgage Payment (P&I)
var monthlyRate = interestRate / 100 / 12;
var numberOfPayments = termYears * 12;
var monthlyMortgage = 0;
if (interestRate === 0) {
monthlyMortgage = loanAmount / numberOfPayments;
} else {
monthlyMortgage = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numberOfPayments)) / (Math.pow(1 + monthlyRate, numberOfPayments) – 1);
}
// Monthly Expenses (Operating)
var monthlyTax = annualTax / 12;
var monthlyInsurance = annualInsurance / 12;
var monthlyMaint = monthlyRent * (maintPercent / 100);
var monthlyVacancy = monthlyRent * (vacancyPercent / 100);
var totalOperatingExpenses = monthlyTax + monthlyInsurance + monthlyHOA + monthlyMaint + monthlyVacancy;
// Total Outflow
var totalMonthlyExpenses = totalOperatingExpenses + monthlyMortgage;
// Net Metrics
var monthlyNOI = monthlyRent – totalOperatingExpenses;
var monthlyCashFlow = monthlyRent – totalMonthlyExpenses;
var annualCashFlow = monthlyCashFlow * 12;
var annualNOI = monthlyNOI * 12;
// Return Metrics
var cashOnCash = 0;
if (totalCashToClose > 0) {
cashOnCash = (annualCashFlow / totalCashToClose) * 100;
}
var capRate = 0;
if (price > 0) {
capRate = (annualNOI / price) * 100;
}
// 4. Update UI
function formatMoney(num) {
return "$" + num.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
}
function formatPercent(num) {
return num.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2}) + "%";
}
document.getElementById("res_cashflow").innerHTML = formatMoney(monthlyCashFlow);
// Change color of cashflow if negative
document.getElementById("res_cashflow").style.color = monthlyCashFlow >= 0 ? "#27ae60" : "#c0392b";
document.getElementById("res_noi").innerHTML = formatMoney(monthlyNOI);
document.getElementById("res_mortgage").innerHTML = formatMoney(monthlyMortgage);
document.getElementById("res_expenses").innerHTML = formatMoney(totalMonthlyExpenses);
document.getElementById("res_coc").innerHTML = formatPercent(cashOnCash);
document.getElementById("res_cap").innerHTML = formatPercent(capRate);
document.getElementById("res_cash_close").innerHTML = formatMoney(totalCashToClose);
document.getElementById("rpc_results").style.display = "block";
}
Purchase Information
Loan Details
Income & Expenses
Please enter valid numbers for all fields.
Monthly Cash Flow:
Monthly Net Operating Income (NOI):
Monthly Mortgage Payment (P&I):
Total Monthly Expenses (w/ Mortgage):
Cash on Cash Return:
Cap Rate:
Total Cash To Close:
Understanding Your Rental Property Analysis
Investing in real estate is a powerful way to build wealth, but the difference between a good investment and a money pit often comes down to the numbers. This Rental Property Cash Flow Calculator helps investors analyze the potential profitability of a residential real estate purchase.
Key Metrics Explained
- Monthly Cash Flow: This is the net amount of profit you pocket each month after all operating expenses and mortgage payments are made. Positive cash flow is essential for long-term sustainability.
- Net Operating Income (NOI): This calculates the profitability of the property before adding in the cost of financing (mortgage). It equals Total Income minus Operating Expenses.
- Cash on Cash Return: Perhaps the most critical metric for investors, this percentage shows the annual return on the actual cash you invested (Down Payment + Closing Costs). A common target is 8-12%.
- Cap Rate (Capitalization Rate): This measures the natural rate of return on the property assuming you paid all cash. It helps compare properties regardless of financing terms.
How to Improve Cash Flow
If the calculator shows negative or low cash flow, consider negotiating a lower purchase price, increasing the down payment to lower the mortgage, or looking for ways to increase rental income (e.g., renovations). Remember to account for realistic vacancy rates and maintenance costs to avoid surprises.