Total Initial Cash Invested (Est. Down Payment)$0.00
function calculateRental() {
// 1. Get Values
var price = parseFloat(document.getElementById("rp_price").value);
var downPercent = parseFloat(document.getElementById("rp_down").value);
var rate = parseFloat(document.getElementById("rp_rate").value);
var term = parseFloat(document.getElementById("rp_term").value);
var rent = parseFloat(document.getElementById("rp_rent").value);
var taxes = parseFloat(document.getElementById("rp_taxes").value);
var insurance = parseFloat(document.getElementById("rp_insurance").value);
var hoa = parseFloat(document.getElementById("rp_hoa").value);
var vacancyPercent = parseFloat(document.getElementById("rp_vacancy").value);
var repairsPercent = parseFloat(document.getElementById("rp_repairs").value);
var capexPercent = parseFloat(document.getElementById("rp_capex").value);
var managementPercent = parseFloat(document.getElementById("rp_management").value);
var errorDiv = document.getElementById("rp_error");
var resultDiv = document.getElementById("rp-result");
// 2. Validation
if (isNaN(price) || isNaN(downPercent) || isNaN(rate) || isNaN(term) ||
isNaN(rent) || isNaN(taxes) || isNaN(insurance) || isNaN(hoa) ||
isNaN(vacancyPercent) || isNaN(repairsPercent) || isNaN(capexPercent) || isNaN(managementPercent)) {
errorDiv.style.display = "block";
resultDiv.style.display = "none";
return;
}
errorDiv.style.display = "none";
// 3. Calculation Logic
// Mortgage
var downPayment = price * (downPercent / 100);
var loanAmount = price – downPayment;
var monthlyRate = (rate / 100) / 12;
var totalPayments = term * 12;
var mortgagePayment = 0;
if (rate === 0) {
mortgagePayment = loanAmount / totalPayments;
} else {
mortgagePayment = loanAmount * (monthlyRate * Math.pow(1 + monthlyRate, totalPayments)) / (Math.pow(1 + monthlyRate, totalPayments) – 1);
}
// Expenses
var monthlyTaxes = taxes / 12;
var monthlyInsurance = insurance / 12;
var vacancyCost = rent * (vacancyPercent / 100);
var repairsCost = rent * (repairsPercent / 100);
var capexCost = rent * (capexPercent / 100);
var managementCost = rent * (managementPercent / 100);
var totalMonthlyExpenses = monthlyTaxes + monthlyInsurance + hoa + vacancyCost + repairsCost + capexCost + managementCost;
// Results
var monthlyCashFlow = rent – mortgagePayment – totalMonthlyExpenses;
var annualCashFlow = monthlyCashFlow * 12;
// Cash on Cash Return
// Note: This is a simplified calculation assuming closing costs are 3% of purchase price approximately, or just using down payment for raw estimate.
// For strictness, let's just use Down Payment as "Cash Invested" to be conservative unless we add a closing costs field.
// Let's add a fixed 3% closing cost estimate to make it realistic.
var closingCosts = price * 0.03;
var totalInvested = downPayment + closingCosts;
var cashOnCash = (annualCashFlow / totalInvested) * 100;
// 4. Update UI
document.getElementById("res_income").innerText = "$" + rent.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("res_mortgage").innerText = "$" + mortgagePayment.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("res_expenses").innerText = "$" + totalMonthlyExpenses.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
var cfElement = document.getElementById("res_cashflow");
cfElement.innerText = "$" + monthlyCashFlow.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
if (monthlyCashFlow >= 0) {
cfElement.style.color = "#27ae60";
} else {
cfElement.style.color = "#c0392b";
}
document.getElementById("res_annual_cf").innerText = "$" + annualCashFlow.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("res_coc").innerText = cashOnCash.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2}) + "%";
document.getElementById("res_invested").innerText = "$" + downPayment.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
resultDiv.style.display = "block";
}
Mastering Rental Property Cash Flow Analysis
Investing in real estate is one of the most reliable ways to build wealth, but the difference between a successful investment and a financial burden often comes down to one metric: Cash Flow. This calculator is designed to help real estate investors strictly analyze the viability of a potential rental property purchase.
What is Rental Property Cash Flow?
Cash flow is the net amount of money left over each month after all operating expenses and mortgage payments have been deducted from the rental income. Positive cash flow means the property is putting money into your pocket, while negative cash flow means you are paying monthly to hold the property.
How to Use This Calculator
To get an accurate result, you need to account for more than just the mortgage. This tool breaks expenses down into three categories:
Fixed Expenses: These are costs that remain relatively constant, such as property taxes, insurance premiums, and HOA fees.
Variable Expenses: These are estimated as percentages of the rent. They include vacancy (months the unit sits empty), maintenance (routine repairs), and CapEx (Capital Expenditures for big-ticket items like a new roof or HVAC).
Debt Service: The principal and interest payments on your loan.
Understanding the Metrics
1. Cash on Cash Return (CoC)
The Cash on Cash return is arguably the most important metric for buy-and-hold investors. It measures the annual return on the actual cash you invested (Down Payment + Closing Costs). A common target for investors is between 8% and 12%, though this varies by market.
2. The 50% Rule
A "rule of thumb" in real estate is that operating expenses (excluding the mortgage) will average out to about 50% of the gross rent over time. While this calculator provides a more detailed breakdown, if your calculated expenses are significantly lower than 50% of the rent, ensure you aren't underestimating maintenance or vacancy costs.
Why Negative Cash Flow happens
Properties often show negative cash flow if the purchase price is too high relative to the rent (low Cap Rate), or if the leverage (loan interest) is too high. If your calculation shows red, consider negotiating a lower purchase price, increasing the down payment to lower the mortgage, or looking for ways to increase the rental income.