.rpc-calculator-wrapper {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 0 auto;
padding: 20px;
background: #f9f9f9;
border: 1px solid #e1e1e1;
border-radius: 8px;
}
.rpc-calc-header {
text-align: center;
margin-bottom: 30px;
}
.rpc-calc-header h2 {
color: #2c3e50;
margin-bottom: 10px;
}
.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;
margin-bottom: 5px;
font-weight: 600;
color: #555;
font-size: 14px;
}
.rpc-input-group input {
width: 100%;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
box-sizing: border-box; /* Important for padding */
font-size: 16px;
}
.rpc-section-title {
grid-column: 1 / -1;
font-size: 18px;
font-weight: bold;
color: #2980b9;
border-bottom: 2px solid #2980b9;
padding-bottom: 5px;
margin-top: 10px;
margin-bottom: 10px;
}
.rpc-btn-container {
grid-column: 1 / -1;
text-align: center;
margin-top: 20px;
}
button.rpc-calculate-btn {
background-color: #27ae60;
color: white;
border: none;
padding: 15px 30px;
font-size: 18px;
font-weight: bold;
border-radius: 5px;
cursor: pointer;
transition: background 0.3s;
}
button.rpc-calculate-btn:hover {
background-color: #219150;
}
.rpc-results-box {
grid-column: 1 / -1;
background: #fff;
padding: 25px;
border-radius: 8px;
border: 1px solid #ddd;
margin-top: 20px;
display: none; /* Hidden by default */
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}
.rpc-result-row {
display: flex;
justify-content: space-between;
margin-bottom: 10px;
font-size: 16px;
}
.rpc-result-row.highlight {
font-weight: bold;
color: #2c3e50;
font-size: 18px;
border-top: 1px solid #eee;
padding-top: 10px;
margin-top: 10px;
}
.rpc-positive { color: #27ae60; }
.rpc-negative { color: #c0392b; }
/* Content Styles */
.rpc-content-wrapper {
max-width: 800px;
margin: 40px auto;
line-height: 1.6;
color: #333;
}
.rpc-content-wrapper h2 {
color: #2c3e50;
margin-top: 30px;
}
.rpc-content-wrapper p {
margin-bottom: 15px;
}
.rpc-content-wrapper ul {
margin-bottom: 15px;
padding-left: 20px;
}
function calculateRentalCashFlow() {
// 1. Get Values
var price = parseFloat(document.getElementById('rpcPurchasePrice').value);
var downPayment = parseFloat(document.getElementById('rpcDownPayment').value);
var closingCosts = parseFloat(document.getElementById('rpcClosingCosts').value);
var rehabCosts = parseFloat(document.getElementById('rpcRehabCosts').value);
var interestRate = parseFloat(document.getElementById('rpcInterestRate').value);
var termYears = parseFloat(document.getElementById('rpcLoanTerm').value);
var monthlyRent = parseFloat(document.getElementById('rpcMonthlyRent').value);
var annualTax = parseFloat(document.getElementById('rpcAnnualTax').value);
var annualInsurance = parseFloat(document.getElementById('rpcAnnualInsurance').value);
var monthlyHOA = parseFloat(document.getElementById('rpcMonthlyHOA').value);
var vacancyRate = parseFloat(document.getElementById('rpcVacancyRate').value);
var maintenanceRate = parseFloat(document.getElementById('rpcMaintenanceRate').value);
// Validation
if (isNaN(price) || isNaN(downPayment) || isNaN(interestRate) || isNaN(termYears) || isNaN(monthlyRent)) {
alert("Please fill in all required fields (Purchase Price, Down Payment, Rate, Term, Rent).");
return;
}
// Set defaults if empty
if (isNaN(closingCosts)) closingCosts = 0;
if (isNaN(rehabCosts)) rehabCosts = 0;
if (isNaN(annualTax)) annualTax = 0;
if (isNaN(annualInsurance)) annualInsurance = 0;
if (isNaN(monthlyHOA)) monthlyHOA = 0;
if (isNaN(vacancyRate)) vacancyRate = 0;
if (isNaN(maintenanceRate)) maintenanceRate = 0;
// 2. Calculations
var loanAmount = price – downPayment;
// Mortgage P&I Calculation
// M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1 ]
var monthlyRate = (interestRate / 100) / 12;
var numberOfPayments = termYears * 12;
var monthlyPI = 0;
if (interestRate === 0) {
monthlyPI = loanAmount / numberOfPayments;
} else {
monthlyPI = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numberOfPayments)) / (Math.pow(1 + monthlyRate, numberOfPayments) – 1);
}
// Operating Expenses
var monthlyTax = annualTax / 12;
var monthlyInsurance = annualInsurance / 12;
var monthlyVacancy = monthlyRent * (vacancyRate / 100);
var monthlyMaintenance = monthlyRent * (maintenanceRate / 100);
var totalMonthlyExpenses = monthlyPI + monthlyTax + monthlyInsurance + monthlyHOA + monthlyVacancy + monthlyMaintenance;
// Cash Flow
var monthlyCashFlow = monthlyRent – totalMonthlyExpenses;
var annualCashFlow = monthlyCashFlow * 12;
// Investment Returns
var totalCashInvested = downPayment + closingCosts + rehabCosts;
var cashOnCashReturn = (annualCashFlow / totalCashInvested) * 100;
// Cap Rate = (Net Operating Income / Current Market Value)
// NOI = Annual Rent – Operating Expenses (excluding mortgage)
var annualOperatingExpenses = (monthlyTax + monthlyInsurance + monthlyHOA + monthlyVacancy + monthlyMaintenance) * 12;
var annualNOI = (monthlyRent * 12) – annualOperatingExpenses;
var capRate = (annualNOI / price) * 100;
// 3. Display Results
var resultBox = document.getElementById('rpcResult');
resultBox.style.display = 'block';
document.getElementById('resMortgage').innerText = '$' + monthlyPI.toFixed(2);
document.getElementById('resExpenses').innerText = '$' + totalMonthlyExpenses.toFixed(2);
var cfElement = document.getElementById('resCashFlow');
cfElement.innerText = '$' + monthlyCashFlow.toFixed(2);
cfElement.className = monthlyCashFlow >= 0 ? 'rpc-positive' : 'rpc-negative';
var annualCfElement = document.getElementById('resAnnualCashFlow');
annualCfElement.innerText = '$' + annualCashFlow.toFixed(2);
annualCfElement.className = annualCashFlow >= 0 ? 'rpc-positive' : 'rpc-negative';
document.getElementById('resCashInvested').innerText = '$' + totalCashInvested.toFixed(2);
var cocElement = document.getElementById('resCoCReturn');
cocElement.innerText = cashOnCashReturn.toFixed(2) + '%';
cocElement.className = cashOnCashReturn >= 0 ? 'rpc-positive' : 'rpc-negative';
document.getElementById('resCapRate').innerText = capRate.toFixed(2) + '%';
}
Understanding the Rental Property Cash Flow Calculator
Investing in real estate is one of the most reliable ways to build wealth, but simply buying a property doesn't guarantee a profit. The difference between a successful investment and a financial burden often comes down to the numbers. This Rental Property Cash Flow Calculator is designed to help investors accurately predict the profitability of a potential rental property before signing on the dotted line.
How Cash Flow is Calculated
Cash flow is the net income from a real estate investment after all mortgage payments and operating expenses have been made. The formula used in this tool is:
- Gross Income: Your projected monthly rent.
- Operating Expenses: Property taxes, insurance, HOA fees, vacancy reserves, and maintenance costs.
- Debt Service: Your monthly Principal and Interest (P&I) mortgage payment.
- Cash Flow = Gross Income – (Operating Expenses + Debt Service)
Why Cash on Cash Return Matters
While cash flow tells you how much money you put in your pocket every month, Cash on Cash (CoC) Return tells you how hard your money is working. It measures the annual return on the actual cash you invested, rather than the total loan amount.
For example, if you invest $50,000 in a down payment and repairs, and the property generates $5,000 in positive cash flow per year, your CoC return is 10%. This metric allows you to compare real estate against other investment vehicles like stocks or bonds.
Example Scenario
Let's say you are looking at a single-family home with a Purchase Price of $200,000.
- You put a 20% Down Payment of $40,000.
- Your Interest Rate is 6.5% on a 30-year term.
- The Monthly Rent is $1,800.
- Annual Taxes are $3,000 and Insurance is $1,000.
Using our calculator, you would find that your mortgage payment is roughly $1,011. After adding taxes, insurance, and setting aside 5% for repairs and vacancy, your total expenses might hover around $1,500. This leaves you with a positive monthly cash flow of approximately $300, or $3,600 per year.
Key Terms Defined
Cap Rate (Capitalization Rate): This metric evaluates the profitability of a property irrespective of financing. It is calculated by dividing the Net Operating Income (NOI) by the property's current market value. A higher Cap Rate generally indicates a better return, though often with higher risk.
Vacancy Rate: No property is occupied 100% of the time. Prudent investors set aside 5% to 10% of monthly rent to cover periods when the property sits empty between tenants.
Use this tool to analyze multiple scenarios by adjusting the purchase price or rent to see exactly what is required to meet your investment goals.