#rental-property-calculator-wrapperBox {
background: #f9fafb;
padding: 25px;
border-radius: 8px;
box-shadow: 0 2px 4px rgba(0,0,0,0.05);
margin-bottom: 40px;
}
.rpc-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
@media (max-width: 600px) {
.rpc-grid { grid-template-columns: 1fr; }
}
.rpc-input-group {
margin-bottom: 15px;
}
.rpc-input-group label {
display: block;
font-weight: 600;
margin-bottom: 5px;
color: #333;
font-size: 14px;
}
.rpc-input-group input {
width: 100%;
padding: 10px;
border: 1px solid #ddd;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.rpc-input-group input:focus {
border-color: #2271b1;
outline: none;
}
.rpc-section-title {
grid-column: 1 / -1;
font-size: 18px;
font-weight: 700;
color: #2c3e50;
margin-top: 10px;
margin-bottom: 10px;
border-bottom: 2px solid #eee;
padding-bottom: 5px;
}
button#rpc-calculate-btn {
background-color: #2271b1;
color: white;
border: none;
padding: 12px 24px;
font-size: 16px;
font-weight: bold;
border-radius: 4px;
cursor: pointer;
width: 100%;
margin-top: 10px;
transition: background-color 0.2s;
}
button#rpc-calculate-btn:hover {
background-color: #135e96;
}
#rpc-results {
margin-top: 25px;
padding: 20px;
background-color: #fff;
border: 1px solid #e5e5e5;
border-radius: 6px;
display: none;
}
.rpc-result-row {
display: flex;
justify-content: space-between;
align-items: center;
padding: 10px 0;
border-bottom: 1px solid #f0f0f0;
}
.rpc-result-row:last-child {
border-bottom: none;
}
.rpc-result-label {
font-weight: 500;
color: #555;
}
.rpc-result-value {
font-weight: 700;
font-size: 18px;
color: #2c3e50;
}
.rpc-highlight {
color: #27ae60;
}
.rpc-highlight-negative {
color: #c0392b;
}
.rpc-article h2 {
margin-top: 30px;
color: #2c3e50;
font-size: 24px;
}
.rpc-article p {
line-height: 1.6;
color: #444;
margin-bottom: 15px;
}
.rpc-article ul {
margin-bottom: 15px;
padding-left: 20px;
}
.rpc-article li {
margin-bottom: 8px;
color: #444;
}
function calculateRentalCashFlow() {
// Get Input Values
var purchasePrice = parseFloat(document.getElementById('purchasePrice').value) || 0;
var monthlyRent = parseFloat(document.getElementById('monthlyRent').value) || 0;
var vacancyRate = parseFloat(document.getElementById('vacancyRate').value) || 0;
var otherIncome = parseFloat(document.getElementById('otherIncome').value) || 0;
var mortgagePayment = parseFloat(document.getElementById('mortgagePayment').value) || 0;
var propertyTax = parseFloat(document.getElementById('propertyTax').value) || 0;
var insurance = parseFloat(document.getElementById('insurance').value) || 0;
var maintenance = parseFloat(document.getElementById('maintenance').value) || 0;
var propertyManagement = parseFloat(document.getElementById('propertyManagement').value) || 0;
var hoaFees = parseFloat(document.getElementById('hoaFees').value) || 0;
var downPayment = parseFloat(document.getElementById('downPayment').value) || 0;
var closingCosts = parseFloat(document.getElementById('closingCosts').value) || 0;
// 1. Calculate Effective Gross Income
// Vacancy is lost rent, not usually applied to other income
var vacancyLoss = monthlyRent * (vacancyRate / 100);
var effectiveIncome = (monthlyRent – vacancyLoss) + otherIncome;
// 2. Calculate Total Expenses
var totalExpenses = mortgagePayment + propertyTax + insurance + maintenance + propertyManagement + hoaFees;
// 3. Calculate Cash Flow
var monthlyCashFlow = effectiveIncome – totalExpenses;
var annualCashFlow = monthlyCashFlow * 12;
// 4. Calculate Total Cash Invested
var totalCashInvested = downPayment + closingCosts;
// 5. Calculate Cash on Cash ROI
var cocRoi = 0;
if (totalCashInvested > 0) {
cocRoi = (annualCashFlow / totalCashInvested) * 100;
}
// 6. Calculate Cap Rate
// Cap Rate = (Net Operating Income / Current Asset Value) * 100
// NOI excludes mortgage (debt service)
var operatingExpenses = propertyTax + insurance + maintenance + propertyManagement + hoaFees;
var annualNOI = (effectiveIncome – operatingExpenses) * 12;
var capRate = 0;
if (purchasePrice > 0) {
capRate = (annualNOI / purchasePrice) * 100;
}
// Format Logic
var formatter = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
});
// Update DOM
document.getElementById('res-eff-income').textContent = formatter.format(effectiveIncome);
document.getElementById('res-total-expenses').textContent = formatter.format(totalExpenses);
var cfElement = document.getElementById('res-monthly-cf');
cfElement.textContent = formatter.format(monthlyCashFlow);
if(monthlyCashFlow >= 0) {
cfElement.className = "rpc-result-value rpc-highlight";
} else {
cfElement.className = "rpc-result-value rpc-highlight-negative";
}
var acfElement = document.getElementById('res-annual-cf');
acfElement.textContent = formatter.format(annualCashFlow);
if(annualCashFlow >= 0) {
acfElement.className = "rpc-result-value rpc-highlight";
} else {
acfElement.className = "rpc-result-value rpc-highlight-negative";
}
document.getElementById('res-coc-roi').textContent = cocRoi.toFixed(2) + "%";
document.getElementById('res-cap-rate').textContent = capRate.toFixed(2) + "%";
// Show Results
document.getElementById('rpc-results').style.display = 'block';
}
Understanding Rental Property Cash Flow
Investing in real estate is a powerful way to build wealth, but the success of any rental investment hinges on one critical metric: Cash Flow. Our Rental Property Calculator helps investors analyze the potential profitability of a real estate deal by accounting for income, vacancies, and all operating expenses.
What is Positive Cash Flow?
Positive cash flow occurs when a property's gross annual income exceeds all operating expenses and debt service payments (mortgage). In essence, it is the profit you pocket every month after paying the bills. Properties with positive cash flow are generally considered safer investments because they pay for themselves and provide a passive income stream.
How to Calculate Cash on Cash Return
While cash flow tells you the dollar amount you earn, the Cash on Cash Return (CoC) tells you how hard your money is working. It compares your annual pre-tax cash flow to the total cash invested.
The formula used in this calculator is:
- Cash on Cash Return = (Annual Cash Flow / Total Cash Invested) x 100%
Total Cash Invested includes your down payment, closing costs, and any immediate repair or rehab costs. A CoC return of 8-12% is often considered a solid benchmark for rental properties, though this varies by market.
The Importance of Vacancy Rate
New investors often make the mistake of assuming a property will be rented 365 days a year. However, turnover is inevitable. This calculator includes a Vacancy Rate input to account for periods where the unit sits empty. A standard conservative estimate is 5% to 8%, representing roughly 2 to 4 weeks of vacancy per year.
Cap Rate vs. Cash on Cash
This tool calculates both. The Cap Rate (Capitalization Rate) measures the property's natural rate of return without considering debt (mortgage). It allows you to compare the profitability of two different properties regardless of how they are financed. In contrast, Cash on Cash Return is specific to your financing structure and actual out-of-pocket investment.