How to Project Rental Property Cash Flow

Your agent says the rental yield is 3.5%. But after mortgage payments, MCST, property tax, insurance, agent fees, vacancy, and income tax, what is your actual monthly cash flow? Is it positive or negative? And how many years until your cumulative cash flow turns positive?

The Cash Flow Projection Tool answers these questions year by year across three scenarios — optimistic, base, and pessimistic — so you know the best and worst cases before you commit.

What This Calculator Does

Project year-by-year rental cash flow across three scenarios — optimistic, base, and pessimistic. See when your cumulative cash flow turns positive, compare ROI at years 5 and 10, and stress-test your investment thesis with different rent, appreciation, and vacancy assumptions.

You can find this calculator in the Calculators tab on ShiokNest. It updates results instantly as you adjust inputs — no waiting, no page reloads.

Why This Matters

Gross rental yield does not equal cash flow. Many properties with attractive headline yields of 3-4% are actually cash-flow negative month after month once you factor in mortgage payments, IRAS property taxproperty tax, maintenance, and vacancy. This calculator matters because:

• It separates yield (paper return) from cash flow (money in your bank account)
• Three scenarios (optimistic, base, pessimistic) show the range of possible outcomes
• Year-by-year projections reveal when cumulative cash flow turns positive

What You Will Discover

After running this calculator with your personal numbers, you will know:

• Year-by-year cash flow across three scenarios (optimistic, base, pessimistic)
• The break-even year when cumulative cash flow turns positive
• ROI at years 5 and 10 under each scenario
• Monthly carrying costs including mortgage, tax, and maintenance
• Whether your investment survives the pessimistic scenario without external top-ups

Key Inputs Explained

Here are the inputs you will configure, along with their default values. Each default is calibrated to a realistic Singapore condo scenario so you can explore results immediately.

Step-by-Step Guide

1. 🏠 Navigate to Calculators — Click the "Calculators" tab in the ShiokNest navigation bar. All 26 calculators are grouped by purpose for easy access.
2. 🔍 Select the calculator — Choose "How to Project Rental Property Cash Flow" from the calculator list. You will see default values already loaded so you can explore immediately.
3. ✏️ Enter your values — Replace the defaults with your own numbers. The key fields are:
   • Purchase Price — The total property price before additional costs.
   • Down Payment (%) — Your cash/CPF contribution as % of price.
   • Interest Rate (%) — Annual loan interest rate.
   • Loan Tenure (Years) — Duration of the mortgage loan.
   • Monthly Rent — Expected monthly rental income or rent you would pay.
4. 📊 Review the results — The calculator updates instantly as you change any input. Year-by-year cash flow across 3 scenarios, break-even year, and ROI at years 5 and 10.
5. 🔄 Run what-if scenarios — This is where the real power lies. Change one variable at a time to see its impact. For example, try increasing the interest rate by 1% or extending your holding period by 5 years. Note how the results shift.
6. 💾 Compare and decide — Run 2-3 different scenarios and note the results. This gives you a range of outcomes to base your decision on, rather than relying on a single projection.

Worked Example

Meet Marcus, buying a $1,500,000 condo for rental investment at $4,500/month. He puts 25% down and takes a 25-year loan at 3.5%. Is this property cash-flow positive?

The three-scenario reality: Marcus's investment looks viable in the optimistic scenario, but the pessimistic scenario (lower rent, higher vacancy) turns cash-flow negative. The calculator projects these year by year, showing when cumulative cash flow turns positive and what ROI looks like at years 5 and 10.

Real-World Scenarios to Try

Here are some realistic scenarios you can plug into the calculator right now. Each one reflects a common situation Singapore property buyers face.

Expert Tips and Common Pitfalls

💡 Pro Tips

• Use realistic assumptions — Singapore condo appreciation has historically averaged 2-4% per year. Avoid overly optimistic projections. When in doubt, use 3% as a baseline.
• Be conservative with vacancy — Even in a hot rental market, budget for 1-2 months vacancy between tenants. A 5% vacancy assumption is the minimum.
• Factor in MCST increases — Condo maintenance fees rise 3-5% per year on average. The pessimistic scenario should reflect this reality.
• Do not rely on the optimistic scenario — The base and pessimistic scenarios are where your investment thesis needs to survive. If it only works in the best case, it is too risky.

⚠️ Common Pitfalls

• Using gross yield as a proxy for cash flow — A 3% gross yield property can still be deeply cash-flow negative after mortgage, tax, and maintenance.
• Ignoring capital expenditure — Major repairs (aircon replacement, waterproofing) happen every 5-7 years and are not covered by MCST fees.

🤔 What-If Scenarios to Explore

Get the most value from this calculator by testing these scenarios:

• Compare a high-rent OCR condo ($3K/month) vs a premium CCR unit ($6K/month) — which has better cash flow?
• What if vacancy rises to 15% due to oversupply? Does your investment survive the pessimistic scenario?
• What if interest rates jump to 5%? How many years until break-even?
• Run at least 3 scenarios — best case, base case, and worst case — to understand the full range of outcomes.

Related Calculators

Your property journey involves many interconnected decisions. These calculators work hand-in-hand with this one:

• How to Calculate Buy-to-Rent ROI
• How to Use the End-to-End Investment Calculator
• How to Optimize Your Holding Period

This how-to guide is auto-generated using ShiokNest's calculator defaults. All worked examples use default values — adjust inputs to match your personal scenario for accurate results.