/* Calculator Styles */
#rental-calc-wrapper {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 20px auto;
padding: 25px;
background: #f9f9f9;
border: 1px solid #e0e0e0;
border-radius: 8px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}
#rental-calc-wrapper h2 {
text-align: center;
color: #2c3e50;
margin-bottom: 25px;
}
.calc-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
.calc-section {
background: #ffffff;
padding: 15px;
border-radius: 6px;
border: 1px solid #eee;
}
.calc-section h3 {
font-size: 16px;
color: #34495e;
margin-top: 0;
margin-bottom: 15px;
border-bottom: 2px solid #3498db;
padding-bottom: 5px;
}
.input-group {
margin-bottom: 15px;
}
.input-group label {
display: block;
font-size: 14px;
margin-bottom: 5px;
color: #555;
font-weight: 600;
}
.input-group input {
width: 100%;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
box-sizing: border-box;
font-size: 14px;
}
.input-group input:focus {
border-color: #3498db;
outline: none;
}
.btn-calc {
grid-column: 1 / -1;
background-color: #27ae60;
color: white;
border: none;
padding: 15px;
font-size: 18px;
font-weight: bold;
border-radius: 5px;
cursor: pointer;
width: 100%;
margin-top: 10px;
transition: background 0.3s;
}
.btn-calc:hover {
background-color: #219150;
}
#calc-results {
grid-column: 1 / -1;
background: #2c3e50;
color: white;
padding: 20px;
border-radius: 6px;
margin-top: 20px;
display: none; /* Hidden until calculated */
}
.result-row {
display: flex;
justify-content: space-between;
margin-bottom: 10px;
padding-bottom: 10px;
border-bottom: 1px solid rgba(255,255,255,0.2);
}
.result-row:last-child {
border-bottom: none;
margin-bottom: 0;
padding-bottom: 0;
}
.result-row span.label {
font-weight: normal;
font-size: 15px;
}
.result-row span.value {
font-weight: bold;
font-size: 18px;
color: #f1c40f;
}
.highlight-result {
background: rgba(255,255,255,0.1);
padding: 10px;
border-radius: 4px;
margin-top: 10px;
}
.highlight-result span.value {
font-size: 22px;
color: #2ecc71;
}
/* Article Styles */
.seo-article {
max-width: 800px;
margin: 40px auto;
font-family: Georgia, serif;
line-height: 1.6;
color: #333;
}
.seo-article h2 {
font-family: -apple-system, sans-serif;
color: #2c3e50;
margin-top: 30px;
}
.seo-article p {
margin-bottom: 15px;
}
.seo-article ul {
margin-bottom: 20px;
}
.seo-article li {
margin-bottom: 10px;
}
@media (max-width: 600px) {
.calc-grid {
grid-template-columns: 1fr;
}
}
function calculateROI() {
// 1. Get Inputs
var price = parseFloat(document.getElementById('purchasePrice').value) || 0;
var downPerc = parseFloat(document.getElementById('downPayment').value) || 0;
var closing = parseFloat(document.getElementById('closingCosts').value) || 0;
var rate = parseFloat(document.getElementById('interestRate').value) || 0;
var years = parseFloat(document.getElementById('loanTerm').value) || 0;
var rent = parseFloat(document.getElementById('monthlyRent').value) || 0;
var otherInc = parseFloat(document.getElementById('otherIncome').value) || 0;
var tax = parseFloat(document.getElementById('propTax').value) || 0;
var ins = parseFloat(document.getElementById('insurance').value) || 0;
var hoa = parseFloat(document.getElementById('hoa').value) || 0;
var vacPerc = parseFloat(document.getElementById('vacancyRate').value) || 0;
var repPerc = parseFloat(document.getElementById('repairRate').value) || 0;
// 2. Loan Calculations
var downAmount = price * (downPerc / 100);
var loanAmount = price – downAmount;
var monthlyRate = (rate / 100) / 12;
var numPayments = years * 12;
var mortgage = 0;
if (rate > 0 && years > 0) {
mortgage = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, numPayments)) / (Math.pow(1 + monthlyRate, numPayments) – 1);
} else if (rate === 0 && years > 0) {
mortgage = loanAmount / numPayments;
}
// 3. Income & Expense Calculations
var totalMonthlyIncome = rent + otherInc;
// Variable expenses based on income
var vacancyCost = totalMonthlyIncome * (vacPerc / 100);
var repairCost = totalMonthlyIncome * (repPerc / 100);
// Operating Expenses (Excluding Mortgage)
var operatingExpenses = tax + ins + hoa + vacancyCost + repairCost;
// Total Expenses (Including Mortgage)
var totalExpenses = operatingExpenses + mortgage;
// 4. Metrics
var monthlyCashFlow = totalMonthlyIncome – totalExpenses;
var annualCashFlow = monthlyCashFlow * 12;
var annualNOI = (totalMonthlyIncome – operatingExpenses) * 12;
var totalInitialInvestment = downAmount + closing;
var cocReturn = 0;
if (totalInitialInvestment > 0) {
cocReturn = (annualCashFlow / totalInitialInvestment) * 100;
}
var capRate = 0;
if (price > 0) {
capRate = (annualNOI / price) * 100;
}
// 5. Display Results
// Helper to format currency
function fmtMoney(num) {
return "$" + num.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
}
function fmtPerc(num) {
return num.toFixed(2) + "%";
}
document.getElementById('res-cashflow').innerHTML = fmtMoney(monthlyCashFlow);
document.getElementById('res-coc').innerHTML = fmtPerc(cocReturn);
document.getElementById('res-cap').innerHTML = fmtPerc(capRate);
document.getElementById('res-noi').innerHTML = fmtMoney(annualNOI);
document.getElementById('res-exp').innerHTML = fmtMoney(totalExpenses);
document.getElementById('res-mortgage').innerHTML = fmtMoney(mortgage);
// Show result box
document.getElementById('calc-results').style.display = 'block';
// Color coding for Cash Flow
var cfElem = document.getElementById('res-cashflow');
if (monthlyCashFlow >= 0) {
cfElem.style.color = '#2ecc71'; // Green
} else {
cfElem.style.color = '#e74c3c'; // Red
}
}
Understanding Rental Property Cash Flow Analysis
Investing in real estate is one of the most reliable ways to build long-term wealth, but not every property is a good investment. The difference between a profitable asset and a financial liability often comes down to one metric: Cash Flow. This Rental Property Calculator is designed to help investors accurately analyze the potential returns of a real estate investment by accounting for income, operating expenses, and financing costs.
Why Cash Flow is King
Cash flow is the net amount of money moving into and out of your rental business. It is calculated by taking your total monthly rental income and subtracting all expenses, including the mortgage payment. Positive cash flow means the property pays for itself and puts money in your pocket every month. Negative cash flow means you are losing money to hold the property.
Experienced investors prioritize cash flow because it provides a safety margin. If the market dips or vacancies rise, a property with strong positive cash flow can weather the storm better than one that barely breaks even.
Key Metrics Explained
1. Net Operating Income (NOI)
NOI is a fundamental calculation used to analyze the profitability of income-generating real estate investments. It equals all revenue from the property, minus all necessary operating expenses.
Formula: NOI = Real Estate Revenue – Operating Expenses
Note: NOI does not include mortgage payments (principal and interest), capital expenditures, or income taxes. It focuses purely on the property's ability to generate income.
2. Cap Rate (Capitalization Rate)
The Cap Rate helps you compare the return on investment of different properties regardless of how they are financed. It represents the yield of a property over a one-year time horizon assuming the property is purchased with cash.
Formula: Cap Rate = (Net Operating Income / Current Market Value) x 100%
A higher cap rate generally implies a higher potential return but may come with higher risk. In many markets, a cap rate between 5% and 10% is considered good, but this varies significantly by location.
3. Cash on Cash Return (CoC)
This is arguably the most important metric for investors using leverage (mortgages). It measures the annual return on the actual cash you invested (down payment + closing costs), rather than the total price of the property.
Formula: CoC Return = (Annual Pre-Tax Cash Flow / Total Cash Invested) x 100%
For example, if you invest $50,000 cash to buy a $200,000 property and it generates $5,000 in annual cash flow, your Cash on Cash return is 10%. This allows you to compare real estate returns directly against other investments like stocks or bonds.
Common Expenses to Watch Out For
When using this calculator, ensure you don't underestimate your expenses. Here are common pitfalls:
- Vacancy Rate: No property is occupied 100% of the time. A conservative estimate is 5-8% (about 2-3 weeks per year).
- Repairs & Maintenance: Things break. Budgeting 5-10% of monthly rent for ongoing maintenance ensures you have funds ready for a leaky faucet or broken appliance.
- Capital Expenditures (CapEx): While not always a monthly expense, big ticket items like roofs and HVAC systems eventually need replacing. Savvy investors set aside reserves for this.
- Property Management: Even if you plan to self-manage, it's wise to run the numbers with a management fee (typically 8-10%) to see if the deal still works if you decide to outsource later.
Using the 1% Rule
As a quick screening tool, many investors use the "1% Rule." This rule of thumb suggests that for a property to be cash flow positive, the monthly rent should be at least 1% of the purchase price. For example, a $200,000 home should rent for at least $2,000/month.
While the 1% rule is a great filter, it is not a substitute for a detailed analysis using the calculator above. Taxes, HOA fees, and interest rates can drastically alter the final profitability even if the property meets the 1% rule.