Avoid These 7 Mistakes When Buying an Investment Property

Buying an investment property after separation can be one of the smartest moves for building long-term financial security, but it also comes where lenders assess applications differently than they do for owner-occupied homes.

The single most important thing to understand is that lenders calculate borrowing capacity more conservatively for investment loans than for owner-occupied loans, and that difference becomes more pronounced if you're servicing child support or dividing income after divorce. Getting the structure wrong at application stage can mean either paying more than necessary or being knocked back altogether.

Choosing Interest-Only Without Understanding the Serviceability Trade-Off

Interest-only repayments reduce your monthly outgoings, which sounds appealing when you're managing household costs on a single income. But lenders still assess your capacity to service the loan on a principal-and-interest basis, even if you apply for an interest-only period.

Consider a buyer who applies for a loan with a five-year interest-only period. The lender will assess whether that buyer can afford the higher principal-and-interest repayments that kick in after year five. If your income or rental yield doesn't support those future repayments, the application won't proceed. This creates a scenario where you might be able to afford the actual repayments during the interest-only period, but the lender's serviceability calculation says you can't borrow that amount.

Interest-only can still make sense if you're planning to use surplus cashflow to pay down non-deductible debt or build other investments. But it won't artificially inflate how much you can borrow, and in some cases it can reduce your borrowing power if the lender applies a higher assessment rate to interest-only applications.

Assuming Rental Income Counts Dollar-for-Dollar

Lenders do not treat projected rental income the same way they treat your salary. Most will only count 80 per cent of the estimated rent, and some apply a discount as high as 20 per cent depending on the property type and location.

That discount is designed to account for vacancy periods, maintenance costs and the possibility that the property sits empty between tenants. If you're buying in an area with a higher vacancy rate or a property type that's harder to lease, such as a studio apartment in an oversupplied precinct, the lender may apply an even steeper discount or ask for additional evidence that the rent is sustainable.

In our experience, applicants who assume the advertised rental yield will cover the loan often find themselves short when the lender's assessment comes back. The gap between what you think the property will earn and what the lender will credit you with can be several hundred dollars a month, and that shortfall has to be covered by your other income.

Overlooking How Child Support Affects Borrowing Capacity

If you're paying child support, lenders treat it as an ongoing liability that reduces your surplus income. If you're receiving child support, most lenders will include it as income, but only if there's a formal agreement in place and you can demonstrate consistent payment history over at least three months.

Verbal arrangements or irregular payments generally won't be counted. Some lenders also apply a discounting factor to child support income, similar to the way they discount rental income, particularly if the paying party's employment is casual or self-employed.

The practical outcome is that your borrowing capacity may be lower than a borrowing calculator suggests, especially if the calculator doesn't account for these nuances. It's worth getting a proper assessment before you start looking at properties, so you know exactly what you can borrow rather than finding out at application stage that the numbers don't work.

Picking the Wrong Loan Structure for Future Portfolio Growth

Most people buying their first investment property don't think about how the loan structure will affect their ability to buy a second property down the line. But if you plan to expand your property portfolio in the next few years, the way you set up this loan matters.

Taking a loan with a standard offset account might feel flexible, but it can create problems later. If you withdraw funds from the offset for personal use, you reduce the deductible portion of your interest. If you then want to use equity from this property to fund a deposit on a second investment property, you may find that part of the borrowing is no longer deductible because the loan purpose has been muddled.

A cleaner structure involves keeping your investment loan separate from any personal borrowing and avoiding redraw facilities where possible. If you need access to equity later, you can set up a separate split or line of credit secured against the investment property, with the loan purpose documented clearly. That separation makes it much easier to maximise your deductions and keep your tax position straightforward.

Ignoring the Deposit Rules That Apply to Investors

Lenders apply stricter deposit requirements to investment loans than to owner-occupied loans. Most will lend up to 90 per cent of the property value for an investment purchase, but only if you're prepared to pay Lenders Mortgage Insurance. Some lenders cap investment loans at 80 per cent unless you meet specific criteria, such as being a professional in a recognised occupation.

Genuine savings requirements also tend to be higher for investors. Where an owner-occupier might be able to use a gifted deposit or equity from another property without demonstrating a savings history, lenders often require investors to show at least three months of genuine savings, and sometimes six months, particularly if you're applying at a higher loan to value ratio.

If you're planning to use equity from a property you retained after separation, make sure you understand how much equity you can actually access. Lenders will typically lend up to 80 per cent of the existing property's value, minus what you still owe. If that property was refinanced recently to buy out your former partner, there may not be much usable equity left, even if the property has increased in value.

Applying for the Loan Before You Understand the Tax Changes

From the 2027-28 income year, losses from established residential investment properties acquired after 12 May 2026 can only be offset against income from other residential properties, not against your salary or other income. Losses can still be carried forward and used in future years, but the immediate deduction against your wage is no longer available unless you're buying an eligible new build.

If you're buying an established property now, you need to understand that the tax treatment has changed. You can still claim interest, rates, insurance, and other holding costs as deductions, but if those expenses exceed the rental income, the loss doesn't reduce your taxable income from employment. That changes the cashflow equation significantly, particularly in the first few years when the property may be negatively geared.

Eligible new builds, including dwellings constructed on vacant land and projects that increase the number of dwellings on a site, remain exempt from the new rules. Those properties can still be negatively geared in the traditional sense. If you're choosing between an established property and a new build, the tax treatment is now a material factor in the decision, not just a minor consideration.

Failing to Factor in How Lenders Assess Investment Loans Differently

Lenders apply higher scrutiny to investment loan applications than to owner-occupied applications. They assess the loan using a higher interest rate buffer, they apply a discount to rental income, and they apply a higher risk weighting to the loan itself, which can affect the interest rate you're offered.

Some lenders also have internal limits on how much of their lending book can be allocated to investors. If a lender has already hit that limit in a given month, your application may be declined or delayed even if you meet all the serviceability criteria. That's not something you can predict from the outside, but it's one reason why working with a broker who knows which lenders are actively writing investment loans can make a tangible difference to the outcome.

Another common issue is underestimating how much the settlement costs will be. Stamp duty on investment properties is calculated at the standard rate, not the concessional first home buyer rate, and in some states it's higher again if you already own property. You'll also need to budget for building and pest inspections, conveyancing, and potentially body corporate records if you're buying a unit. Those costs can add up to several thousand dollars, and they need to come from savings or available equity, not from the loan itself.

Call one of our team or book an appointment at a time that works for you. We'll run the numbers based on your actual situation, help you understand what different lenders will credit you with, and structure the loan so it supports your goals without locking you into a position that limits your options down the track.

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