Most buyers know their mortgage repayment amount. They punch their loan into a calculator, see the monthly figure, and move forward. But here is what catches them out: the mortgage is only part of your housing costs.
Insurance. Strata fees. Council rates. Maintenance. These costs add up. For a typical Sydney apartment, ongoing costs can add $400-800 per month on top of your mortgage.
This calculator shows you the complete picture. Your total housing outgoings per payment period, combining mortgage repayments with base maintenance costs.
Why Total Housing Costs Matter
Banks calculate your borrowing power using your mortgage repayment. But your actual budget needs to account for everything.
Consider this example:
Property: $800,000 apartment in Sydney
- Loan amount (20% deposit): $640,000
- Interest rate: 6.5%
- Loan term: 30 years
- Monthly mortgage (P&I): $4,046
Most buyers stop here. But add ongoing costs:
- Building insurance: $80/month
- Strata fees: $350/month
- Council rates: $150/month
- Water rates: $40/month
- Maintenance reserve: $130/month
Total monthly housing cost: $4,796
That's $750 more than the mortgage alone. Over a year, it's $9,000 extra you need to budget for. This is why smart buyers use our property investment calculator alongside this tool to model complete ownership costs.
Understanding Payment Frequencies
Australian lenders offer three common payment options:
Monthly Payments Standard option. 12 payments per year. Easiest to budget around monthly income.
Fortnightly Payments 26 payments per year. Each payment is roughly half the monthly amount, but you make 2 extra half-payments annually. This can shave years off your loan.
Weekly Payments 52 payments per year. Similar benefit to fortnightly but split further.
The calculator converts your ongoing costs to match your chosen frequency. If you pay fortnightly, you'll see both mortgage and maintenance as fortnightly figures.
Principal and Interest vs Interest Only
Two repayment types change your cash flow substantially:
Principal and Interest (P&I) Each payment reduces your loan balance. You build equity with every payment. This is the standard for owner-occupiers and most investors.
Interest Only You only pay interest. The loan balance stays the same. Monthly payments are lower, but you're not building equity. Commonly used by investors for tax and cash flow reasons.
Interest-only periods typically run 1-5 years before reverting to P&I. The calculator shows both options so you can compare.
What Counts as Maintenance Base
The maintenance base covers recurring non-mortgage costs:
Building Insurance Covers the structure against fire, storm, and other damage. For units, this is typically included in strata. For houses, budget $1,200-2,500 per year.
Strata or Body Corporate Fees Apartment and townhouse owners pay quarterly strata levies. These cover building insurance, common area maintenance, and a sinking fund for major repairs. Fees range from $600 to $2,000+ per quarter depending on building age and amenities.
Council Rates Local council charges for services. Budget $1,200-2,500 per year depending on property value and location.
Water Rates Fixed and usage charges from your water provider. Budget $400-800 per year.
Maintenance Reserve Set aside money for repairs and upkeep. A common rule: 1% of property value per year. For an $800,000 property, that's $8,000 annually or $667 monthly.
Before buying, always get a building inspection to identify potential maintenance issues.
Using the Calculator Effectively
Step 1: Enter your property details Start with the purchase price and your deposit. The calculator derives your loan amount.
Step 2: Set your loan terms Enter the interest rate your lender quoted. Set your loan term (typically 30 years in Australia). Choose P&I or interest-only.
Step 3: Select payment frequency Pick monthly, fortnightly, or weekly based on how you prefer to pay.
Step 4: Add maintenance costs Enter a single monthly figure combining all ongoing costs. Or expand the breakdown to enter insurance, strata, and maintenance separately.
Step 5: Review total outgoings The calculator shows your complete housing cost per payment period, plus monthly and annual totals.
Comparing Against Your Income
Use your total monthly housing cost to check affordability:
The 30% Rule Traditional advice says housing costs should stay under 30% of gross household income. For a household earning $150,000, that's $3,750/month for all housing costs.
Reality Check In Sydney and Melbourne, many buyers stretch to 35-40% during their early years of ownership. This works if you have career growth ahead, but leaves less buffer for rate rises.
Compare your calculator results against your income. If total housing costs exceed 35% of gross income, consider whether a smaller deposit or different property fits better. First home buyers should also check government home schemes that can reduce upfront costs.
What the Calculator Doesn't Include
This tool focuses on recurring costs. Some expenses sit outside:
One-off Buying Costs Stamp duty, legal fees, building inspections, and moving costs. Our first home buyer guide covers these in detail.
Council Rates and Land Tax Some buyers include council rates in their maintenance figure. Land tax applies to investment properties but not owner-occupied homes.
Utilities Electricity, gas, and internet are user costs rather than property costs.
Capital Improvements Renovations and upgrades beyond maintenance aren't included.
Running Your Numbers
Before committing to a property, run the numbers through this calculator. Know your total monthly outgoing before you sign contracts. This gives you confidence that you can afford the property for the long term.
If you're weighing whether to buy or continue renting, combine this calculator with our rent vs buy calculator to see the complete picture.
Legal Notice
This calculator provides general estimates only. Actual repayments depend on your lender's terms and conditions. Always confirm figures with your lender before making financial decisions.
For personal advice, consult a licensed mortgage broker or financial adviser. Check credentials at ASIC.