Common Mistakes When Owning Multiple Investment Properties

Owning multiple investment properties in Double Bay or nearby suburbs demands a different approach to borrowing and structuring than most investors realise when they buy their first rental.

The debt-to-income limit introduced from February this year means lenders now assess your total borrowing across all properties against your income, not just the next loan in isolation. If you already hold two properties with a combined debt of $2.4 million and earn $200,000, you sit at a DTI of 12 times. Most banks will lend up to 20 per cent of new investor loans to borrowers at six times or greater, but once you pass that threshold serviceability tightens sharply. The buffer sits at 3.0 percentage points above the actual rate, so a 6.5 per cent loan is assessed at 9.5 per cent. That calculation gets harder with each property you add.

Structuring Loans Separately From Day One

Each property should sit on its own loan facility, not cross-collateralised with other assets. Cross-collateralisation allows a lender to use multiple properties as security for a single loan or to hold a mortgage over all properties in your portfolio even when only one secures new borrowing. Once properties are linked this way, you need the lender's consent to sell or refinance any single asset. That constraint becomes a material issue when you want to release equity from one property to fund the next purchase or move a poorly performing loan to a better rate.

Consider an investor who bought a unit in Rushcutters Bay at $1,211,000 using one lender, then added a terrace in Paddington at $3,622,500 with the same institution and allowed both to be cross-secured. When the Paddington loan became uncompetitive two years later, refinancing required the Rushcutters Bay property to either move with it or be formally discharged. The lender refused partial discharge without a full revaluation and a $15,000 break cost on the Paddington fixed portion. Structuring the loans separately from the start would have allowed the investor to move the Paddington debt without touching the other facility.

How Rental Income Is Assessed After Your First Property

Lenders typically shade rental income to between 70 and 80 per cent of the actual figure when calculating serviceability, and some apply a further vacancy adjustment. That shading compounds across multiple properties. If you own three properties each generating $1,000 per week, the lender sees $2,100 to $2,400 in weekly income, not $3,000. The shortfall is made up by your salary, but if your salary is already supporting high principal-and-interest repayments on existing investment loans, the numbers tighten quickly.

Interest-only terms help in the short run by lowering the assessed repayment, but they are typically capped at five years and are non-standard under APRA's framework if the LVR exceeds 80 per cent at the outset. Once the interest-only period expires, repayments increase and your serviceability buffer shrinks unless your income or equity position has improved. Most borrowers with multiple properties refinance or restructure before the expiry date rather than reverting to principal and interest at a higher repayment.

Using Equity Without Refinancing the Whole Portfolio

Growth in one property can fund the deposit for the next, but only if the loan structure allows you to access that equity independently. A standalone equity facility or split loan structure lets you draw against one property without disturbing the rate, term or conditions on the others. If all your properties sit under one lender with cross-collateralisation, accessing equity often means refinancing the entire portfolio, retriggering valuation costs and documentation requirements across every asset.

In our experience, investors who separate their loans by property and lender from the outset retain more flexibility as the portfolio grows. That approach also spreads concentration risk so that a policy change or serviceability tightening at one institution does not lock up the entire portfolio. Equity release becomes a planned step rather than a reactive scramble when the next opportunity appears.

Choosing Between Variable and Fixed Across Multiple Properties

A single-property investor might fix the entire loan for rate certainty, but across multiple properties that approach removes flexibility. Fixed rates carry break costs if you sell or pay down early, and those costs multiply across several properties if you need to exit or restructure during a rising rate environment. A split strategy, where part of each loan is fixed and part remains variable, preserves some ability to make extra repayments or sell without penalty while still locking in a portion of your exposure.

Variable portions also allow offset accounts, which are useful when you are building cash reserves between purchases or setting aside funds for future deposits. Fixed loans do not typically offer offset, so any surplus cash sits outside the loan and continues to accrue interest. With three or four properties, that difference can amount to tens of thousands in unnecessary interest over a few years.

What Negative Gearing Changes Mean for Properties Acquired After May Last Year

Properties acquired after 7:30pm on 12 May last year face a new rule from the 2027-28 income year where rental losses can only be offset against income from other residential properties, not against salary. Losses can still be carried forward to future years and offset against capital gains or rental profits, but the immediate tax benefit against wage income no longer applies. Properties held at that date, including those under contract, remain fully deductible under the old rules until sold. New builds are also exempt and continue to allow full deductibility.

This changes the cashflow equation for investors adding a second or third established property. If you rely on negative gearing to reduce your taxable income each year, properties bought after that date will not deliver that outcome unless you already hold other investment properties generating positive income to absorb the loss. The change does not affect your ability to claim interest as a deduction, it only changes where that deduction can be applied. For self-employed borrowers in Double Bay with variable income, the loss of that offset can affect cashflow timing, particularly in years where rental income lags or vacancy rates increase.

When Lenders Mortgage Insurance Becomes a Repeated Cost

LMI is calculated per loan, not per borrower, so each time you borrow above 80 per cent LVR you pay the premium again. On a $1.5 million loan at 85 per cent LVR, the premium typically sits between $30,000 and $50,000 depending on the lender and your profile. Across three properties, that cost compounds quickly. Some lenders offer LMI waivers for certain professions or allow you to capitalise the premium into the loan, but LMI waivers are rarely available once you move past two properties or exceed a certain portfolio debt level.

The alternative is to wait until you have 20 per cent deposit from a combination of savings and released equity, but that often delays the next purchase by 12 to 18 months. For investors targeting portfolio growth, paying LMI can be the more effective path if the property's expected capital growth exceeds the premium cost over the holding period. The decision depends on your cash position, income stability and the timing of the opportunity.

Why Refinancing One Property Should Not Trigger a Review of the Others

When loans are structured separately and held with different lenders, refinancing one property for a lower rate or better features does not require you to disclose or resubmit serviceability for the entire portfolio. The new lender assesses the loan being refinanced and takes a first mortgage over that property only. Your other loans remain untouched. This is one of the clearest advantages of avoiding cross-collateralisation and spreading your lending across multiple institutions. Investment loan refinancing becomes a targeted exercise rather than a full portfolio reconstruction every time you want to improve one facility.

Call one of our team or book an appointment at a time that works for you. We work with self-employed and professional investors across Double Bay and the eastern suburbs to structure lending that supports portfolio growth without locking you into a single lender or cross-secured position.

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