What to Consider When Buying an Investment Property

An investment property is a tool. Before looking at a property purchase, decide what job it has to do, whether a leveraged house is the right tool for the job, and only then which property, on what terms, at what price. Buyers who begin by looking at property listings usually end up with a property which suited the person selling it.

Decide what the property is for

A rental bought to produce income within a few years is a different purchase from one bought to build capital over decades. A property bought for income needs rent well above its costs from the start, which usually points to a property with a higher yield; a larger deposit reduces the weekly burden but does not make the property itself more productive. A household buying for capital can tolerate an early shortfall, provided the shortfall stays affordable and the expected return over the full holding period justifies it. Most buyers want some of each, and the balance between them shapes which property suits.

Sizing what you will need in retirement, and how much of it a property should supply, is deliberate financial planning. For the property decision a simpler version might do: decide what you want the property to achieve. Decide how much you could afford to put in each year if the rent does not cover the costs, and what you would do with the same deposit, and potentially the same monthly top-up, if you did not invest in property.

Is a leveraged property the right tool?

Property's distinctive benefit is the ability to borrow to invest. A bank will lend most of the price of a house on terms it will not offer against shares or funds, so a 30 percent deposit exposes the owner to the change in value of the whole property. A 5 percent rise in property values adds a sixth to the owner's equity, and a 5 percent fall removes the same sixth. The same mechanism magnifies losses, and it is why the Reserve Bank regulates how much of this lending banks can do.

There are other tools in the modern investor's toolbox, with different strengths and weaknesses. Consider an unleveraged, diversified portfolio with no tenants, no council rates bill and no property insurance:

• Over the 20 years to May 2026, Auckland house prices rose about 4.7 percent a year before rental income, and about 1.6 percent a year over the past 10.
• Global shares returned 9.6 and 15.1 percent a year in New Zealand dollars over the same periods, including dividends, before fees and tax.

These are not like-for-like returns, since property also produces rent and carries costs and usually debt. The comparison remains useful, as it tests the widespread belief in houses reliably outgrowing everything else, and over these periods they have not. Property and shares also differ in liquidity, tax and the work involved.

A property can be the better tool in many cases. Real estate suits an investor who can borrow prudently and hold through a full interest rate cycle, who can add value by renovating, subdividing or building, or who wants a single asset they control and understand. It suits an investor less well when goals such as funding retirement can be met without debt, when the deposit would exhaust their reserves, or when the plan relies on property prices rising at their 20-year pace rather than their 10-year one.

What a bank will lend, and what you should borrow

Most investors borrow against the equity in their own home rather than saving a cash deposit. As a starting estimate, banks will usually lend up to 80 percent of the home's value, so a $1 million home with a $550,000 mortgage carries $250,000 of usable equity: $800,000 less $550,000. Usable equity is borrowing capacity rather than cash. Drawing on it adds debt, with its own interest, and the whole of it counts against the household's income.

Plan on a 30 percent deposit for an existing property. The Reserve Bank's loan-to-value ratio restrictions allow banks to write no more than 10 percent of new investor lending above 70 percent LVR, so a smaller deposit is possible for some borrowers but cannot be counted on. Loans to build a new home, or to buy a newly built one from the developer within six months of completion, sit outside the restriction, and some banks will lend with a 20 percent deposit on their own criteria. A property completed last year and sold by its first owner does not qualify.

Plan on total debt of no more than seven times gross household income. Since 1 July 2024 the Reserve Bank's debt-to-income restrictions have limited banks to 20 percent of new investor lending above that ratio, counting every mortgage, car loan, student loan and credit card limit. New builds, on the same definition, are exempt from the DTI rules as well. For a borrower near the ceiling, the exemption is often a larger advantage than the smaller deposit.

Take a couple who own a $1 million home with a $550,000 mortgage, have a $30,000 car loan and earn $200,000 between them. They are buying a $750,000 existing property, close to the national median sale price, and they borrow the full $750,000, with the home as additional security for the deposit. Total debt after the purchase is $1.33 million, a DTI of 6.7 across both properties, inside the limit. Banks count part of the expected rent as income, discounted for vacancies, management and maintenance. If this bank counts 75 percent of the rent collected, the ratio falls to about 5.9. On a combined income of $160,000 the same structure gives a DTI of 8.3 before rent and 7.2 after it, and the couple are outside the standard rules. Having $250,000 of usable equity does not mean a household can deploy all of it. In our experience advising New Zealand households, DTI has become the binding constraint for many investors. Before the rules arrived, the limit was more often cash flow: whether the household could service the loan at the bank's test rate.

Each bank then applies its own tests: a serviceability rate well above the rate you will pay, called a stress test, its own allowance for living costs and its own treatment of rent. Investors with identical finances can get different answers from different banks, which is one reason to use a mortgage adviser who deals with several. Ask, too, how the loans will be secured. Where the home and the rental secure the same lending, trouble with either loan exposes both, and separate loan accounts do not by themselves separate the securities. A bank's approval confirms the loan fits the bank's rules. Whether the purchase fits your personal financial strategy is a separate and larger question, answered by the cost and likely return of the property itself.

The annual cost of holding a rental

Every property has its own figures, and the reliable ones come from documents: the current rates notice, a written insurance quote, a property manager's fee proposal, a rental appraisal backed by comparable tenancies, a builder's view of the next five years' maintenance needs, and the body corporate accounts where there is one. Rules of thumb can provide a good initial estimate:

• Mortgage interest. Usually the largest cost by a wide margin, and it applies to every dollar borrowed for the purchase. Many investors start on interest-only terms so the rent covers more of the outgoings; principal repayments, when they begin, come on top.
• Council rates. Rates bills rose 8.8 percent nationwide in the year to June 2026. Use the current notice and allow for increases over the holding period.
• Insurance. Landlord cover for the building, loss of rent and liability. Home insurance premiums have risen about 40 percent in two years, on Treasury analysis, and some insurers have withdrawn from flood-exposed suburbs.
• Property management. Commonly charged as a percentage of rent collected, plus GST, usually with separate letting and inspection fees.
• Maintenance. Use a builder's assessment and a multi-year allowance rather than assuming a percentage suits every property. A home being converted from owner-occupied to rental may need work to meet the Healthy Homes standards.
• Body corporate or residents' association levies, for apartments, townhouses and some subdivisions. Read the long-term maintenance plan for the projects it forecasts, the fund balance against them, the planned contribution path and any history of special levies. For a residents' association, check the annual charge, what it maintains and the covenants on the title which bind you to it.
• Vacancy. For planning purposes, account for the property standing empty for a couple of weeks a year between tenants.

To illustrate this, consider the couple's $750,000 property, with an interest-only loan. Say it rents for $650 a week, a little above the national median. Over a full year the contract rent is $33,800, a headline gross yield of 4.5 percent. Allow two vacant weeks and the rent collected is $32,500. Management at 8 percent plus GST on the rent collected is about $3,000; rates $3,500; insurance $3,000; maintenance $5,000 for a sound house. Those four costs take $14,500, leaving about $18,000 before interest and tax. As a percentage of the price, this is the net operating yield: 2.4 percent, roughly what the median Auckland house produces on current figures.

Interest comes next, on the full $750,000 borrowed. At 5.5 percent, it is $41,250 a year. The property therefore loses about $23,200 a year, or $450 a week, paid from after-tax salary. Had the couple put in $225,000 of cash instead of borrowed equity, the loss would be about $10,900, or $210 a week. The difference is the cost of borrowing the deposit, and it is the figure most often left out of a buyer's model. On a principal-and-interest loan the weekly outlay is higher again, although the principal portion reduces debt rather than strictly being accounted for as a cost. Rental losses are ring-fenced for tax, so none of it reduces the tax on their salaries; it is carried forward against the property's future profits, assuming there are some.

Entry and exit costs sit outside the annual figures and belong in the decision. On the purchase there are legal fees, a valuation, a builder's report and loan fees; on the sale, the agent's commission, staging fees, any pre-sale maintenance or touch-ups, and more legal fees. They are property-specific, and over a short holding period they raise the growth the property has to deliver.

Problems rarely arrive one at a time, so test several at once. Raise the interest rate to 7.5 percent, let the property sit empty for four weeks and achieve rent 5 percent below the rental appraisal. Then add a $10,000 repair on top of the routine $5,000 allowance, all in the same year. The loss is then about $50,800 in one year, or nearly $1,000 a week. A one-off repair is paid from reserves and the asset is preserved; a lasting fall in rent or rise in rates changes the investment case itself and calls for a rethink. Can the couple fund $450 a week from surplus income without touching their reserves, and still find $1,000 a week in a bad year? What remains in reserve after the purchase, and would it cover several months of the stressed shortfall and one credible repair? A purchase which passes the bank's tests and fails these questions is generally a purchase to defer.

Does the anticipated return justify the cashflow loss?

A household which can afford to carry a cashflow loss still has to decide whether that loss is worth carrying. How to frame the test depends on how the purchase is funded; whether the property passes depends mainly on the growth it achieves.

With a $225,000 cash deposit, the couple need a return on that money. A hurdle rate is the return an investor requires before accepting an asset's risks. It is personal, and depends on what other investments are available, tax, holding period and how it is measured; the version here is a first-pass test rather than a forecast. Consider the relative safety of long-dated government bonds, which yielded about 5 percent in September 2026. A single house carries risks they do not: one asset, one location, compliance rules such as Healthy Homes, tenants, possible weather events, likely months to sell, and usually mortgage-related risks. A reasonable property investor might therefore ask 9 percent a year before tax. On $225,000 that is $20,250 each year. Add the $10,900 shortfall the investors would be contributing to the property, and the property's value has to rise by about $31,100 a year, or 4.2 percent, to clear the hurdle.

With the deposit borrowed, no cash has been contributed, and the test becomes whether the property earns more than its debt costs. The property yields 2.4 percent before interest and debt costs 5.5 percent on the whole price, so values have to rise 3.1 percent a year merely to offset the gap, before transaction costs and tax. The investor then needs a further margin for concentration, illiquidity, the work involved and the risk placed on the family home, and how large a margin is their call. Either way, at these figures the purchase requires annual growth close to or above Auckland's average over the past 20 years (4.7 percent) and well above its average over the past 10 (1.6 percent).

A property which needs $450 a week from salary before any principal is repaid carries a high evidential burden. Something has to compensate for the weak starting economics: rent well above the appraisal, a purchase below market, or a credible plan to add value. The couple's ability to absorb the loss is a condition of proceeding, and it is no part of the case for proceeding. If the plan only works with growth at the top of the historical range, the plan needs changing. Usually the change is paying less, borrowing less, or buying something with a higher net operating yield, and sometimes it is deciding the deposit does more for the household somewhere else.

Choosing the property

Type of property is a set of trade-offs, and the key aspects are financial: purchase price, realistic net operating yield, the big repairs likely over the holding period, lending treatment, scope to add value and depth of the resale market. Freestanding houses usually cost the most, rent the least relative to price, and offer the most scope to add value, because more of the price is attributed to land. Apartments cost the least to enter and often show the highest gross yields, with body corporate levies, less control and, for small or unusual units, larger deposit requirements in exchange. Townhouses sit between the two, usually with residents' association obligations and, in some large developments, questions over build quality.

The new build or existing choice is usually the most consequential. A qualifying new build brings a lower deposit, the DTI exemption, Healthy Homes compliance from day one, low early maintenance and new fittings and appliances which can be depreciated for tax. An established property usually carries more land relative to the building, which gives more ways to improve the site, and sits in a settled market with proven resale demand. Buildings wear out and need money spent on them, while land holds its physical condition but can still lose value through planning changes, hazards or a weak local market. A large development might deliver dozens of similar homes to one area at once, competing for the same tenants and, potentially later, the same buyers.

Location is where the opportunity lies. Look for long-run population growth, a broad local economy rather than one dominant employer, local incomes which comfortably support the rent you are assuming, and a deep resale market for the type of property you are buying. Alongside the regional picture, check the street-level evidence: how many comparable rentals are advertised now and how quickly they let, and how much competing supply is consented or under construction nearby. Many investors buy in their own suburb because they know it; the trade-off is concentrating the home and the investment in one market and one set of hazards, which diversifying across locations avoids.

Some findings change the decision. The rent assumption may rest on the agent's appraisal rather than on recently let comparable properties and the bond data. An insurer may decline to quote, or quote with a flood or land-movement exclusion. The resale market for the property type may be thin, or a new development large relative to the suburb's existing rental stock. Each is a reason to stop and resolve the issue, and to walk away if it cannot be resolved or priced in. For most people who proceed with direct property, a conventional long-term rental is easier to assess and run than development, repeated renovation or trading, which are small businesses with their own capital, tax and skill requirements.

Checks before going unconditional

An offer on an existing property is usually conditional, which buys time to verify what you are buying. Order the LIM and read it for unconsented work, hazard notations and anything which would trouble an insurer or a future buyer. Commission an independent builder's report and price what it finds. Obtain the insurance quote before going unconditional and confirm the cover satisfies the lender's conditions, because a property which cannot be insured usually cannot be mortgaged. For an apartment or townhouse, read the body corporate minutes for special levies and disputes and check the long-term maintenance fund against the plan. Get the rental appraisal in writing and test it against recently let comparables. For a new build bought off the plans, the checks are different. Look at the developer's completed projects, exactly what the contract includes, and comparable rents for finished homes nearby, and have a property lawyer review the sunset clause, deposit protection and the consequences of delay before signing.

After settlement, plan for refinancing and for the unexpected. When a fixed term ends, a borrower can usually refix with the existing lender without a full new application. Switching banks, increasing the debt or restructuring the lending generally requires a fresh serviceability and DTI assessment, so keep headroom in equity, income and total debt. And keep a cash reserve covering several months of the stressed shortfall and one credible repair, held separately from the deposit and increased where income is variable or the building has known work ahead.

Tax

As is the case with any investment, tax should inform the decision but never drive it. Each of these settings has changed at least once in the past five years, so build a plan which works whichever government is in power.

• Interest deductibility. From 1 April 2025, 100 percent of qualifying interest on money borrowed to buy a residential rental can be claimed against rental income, provided the interest is not private and the general deductibility rules are met. Deductibility follows the use of the borrowed money, not which property secures the loan, which is why investors usually keep the rental borrowing separately identified. Rental loss ring-fencing still applies: a loss cannot be offset against salary or other income, only carried forward against future residential rental income.
• Chattels. The building itself cannot be depreciated, but chattels can: carpets, curtains, appliances, some heat pumps and similar items. On a new build the set is complete and new, and the deduction can be material in the early years. Whether an item is a chattel or part of the building depends on the tax rules, and the opening values must be supportable; a chattels valuation at purchase usually establishes them, and an accountant can confirm the treatment.
• The bright-line test. For property sold on or after 1 July 2024, the bright-line test generally taxes the gain where the bright-line end date falls within two years of the start date, unless the main-home exclusion, another exclusion or rollover relief applies. Other land sale rules, including the intention test, can apply beyond two years. Ownership structure, whether personal, company or trust, affects both tax and lending, and is a question for an accountant before the offer rather than after.

Take action

Confirm your borrowing capacity, then run the cashflow numbers against higher interest rates, lower rent and a vacancy, and ask what growth the property needs to justify the shortfall. The investment should work across a range of scenarios, not only the base case. When you start looking, lead with your head rather than your heart.

Be careful whose numbers you are using. Whoever helps you, ask: are they using an outdated model, based on past returns? How are they paid? Is the person recommending the property also selling it? Has the rent assumption been checked independently? Are they willing to tell you not to buy? Most property investment guidance assumes you should invest in property, which is not always the case.

If you would like help confirming your borrowing position and running the cashflow and hurdle-rate scenarios for a property you are considering, get in touch with our team.